VW motor has kill switch after crash?

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I have a relative that is an insurance adjustor, and she was asking me a question about the VW's. She stated that she has a client that is saying that VW has a engine kill switch after a accident, to prevent engine fires.

So she was asking me if I had heard of that in my Jetta. This is the first that I had heard of something like that, and wasn't even sure if that was truth. But according to this person she was tallking to, she stated that all newer VW's have these. The VW in question is a 2005 Jetta, and not sure what type of motor they have, but I did ask.

Truth, or wool over the eyes?
 

compu_85

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I don't know of any Ford style fuel pump switch. Perhaps when the airbag computer sends an airbag deployment one of the things that happens (along with the doors unlocking) is the engine shutting off? I'm 99% sure my 99.5 does not have this feature, and am 100% sure the A3/B4 cars do not.

-Jason
 

owr084

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If they do, it would have to be prominently mentioned in the manual. I know it was for my 86 T-Bird. But, I don't recall seeing it in any of the manuals for my current vehicles...
 

jettawreck

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The fuel sending unit in the tank on the VE systems has the crude roll-over/shut off valve, I believe. I don't think it's meant to shut off the engine (oil starvation will take care of that soon enough) but to keep fuel from leaking out of severed lines into crash area when inverted. Perhaps the PDs with the electric lift pump have a impact shut off, but never heard of such.
 

FLMan

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My son flipped my old 98 Jetta TDI end over end, the car landed on its passenger side when it finally came to a stop. As he was climbing out the drivers window, he told me that he stopped and had to go back in to shut the key off, because the engine was running and the front wheels were still turning. He faired really well in this accident, his only injury was a VW logo branded into his arm when the air bag deployed. Well, it was dark green and ended up in some pines about a 10th of a mile from our home. No one could see the accident because it was night time on a county road. A friend of mine helped us tow it home on a chain after we put it back on its wheels. Never reported it to the insurance. Sold it for parts on the TDI Club.
 

oilhammer

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Most modern cars, including Volkswagens, have this feature. That is why the SRS module is tied into the CAN system; to tell the other modules the air bags have gone off. So, the engine ECU can shut the engine off, the CCM can unlock the doors, etc.

On pre-CAN A4 cars, I am pretty sure if you follow the path of the wiring for the main ECU relay (relay 109) the SRS module has the ability to de-energize that directly...no CAN bus communications on those.

On most all gas powered VAG cars, the SRS module has the ability to de-energize the electric fuel pump relay directly. The PD TDIs may be the same, I am not sure.
 

concours

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TriDubInventory said:
I have a relative that is an insurance adjustor, and she was asking me a question about the VW's. She stated that she has a client that is saying that VW has a engine kill switch after a accident, to prevent engine fires.

So she was asking me if I had heard of that in my Jetta. This is the first that I had heard of something like that, and wasn't even sure if that was truth. But according to this person she was tallking to, she stated that all newer VW's have these. The VW in question is a 2005 Jetta, and not sure what type of motor they have, but I did ask.

Truth, or wool over the eyes?
ALL fuel injected gas engined vehicles REGARDLESS of brand, have a federally mandated inertia switch to prevent fuel from being pumped at an accident scene after broken lines. The conventional diesel engines fuel pump is mechanically driven and is inherintly safe. The PD engine's electric lift pump must also have an inertia switch built in to it's circuit.
 

FLMan

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concours said:
ALL fuel injected gas engined vehicles REGARDLESS of brand, have a federally mandated inertia switch to prevent fuel from being pumped at an accident scene after broken lines. The conventional diesel engines fuel pump is mechanically driven and is inherintly safe. The PD engine's electric lift pump must also have an inertia switch built in to it's circuit.
Why didn't the 98 TDI shut down after multiple flipping?
 

compu_85

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Like I said.. because the airbags are not linked to the ECU on the A3 cars.

I saw a youtube video of some wackos abusing a (what I assume was a 2.0) A3, they hit a jump, and the airbags went off when they landed, but they just kept on driving.

-J
 

mrGutWrench

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FLMan said:
My son flipped my old 98 Jetta TDI end over end, the car landed on its passenger side when it finally came to a stop. (snip)
__. My '02 Jetta sedan rolled "side to side", slid down the ditch (the policeman measure a little over 60 feet that its roof made a mark down the ditch, then dug in and flipped end over end. The side air bags were in place before the driver's outside mirror tried to come in the window and hit me in the head (it didn't) and before we were upside down sliding down the ditch (I remember thinking, "am I better off holding on the the steering wheel to keep from hitting my head or should I let go with one hand and put my forearm between my head and the roof of the car ... and it this a towel wrapped around my head? Where did this come from. Oh, if I can come through this without hitting my head, I *might* be OK."

__. After it flipped end over end, it landed on it's wheels. The engine was still running. I switched it off - I remember it clearly. I never thought about it before but a policeman opened the passenger's door (the car was sitting on the bottom edge of the driver's door in the ditch and the door wouldn't open). I had already started to crawl out the passenger's side when the cop opened the door. I don't think that I unlocked the doors. So, if I remember it right, the engine didn't shut off and the doors unlocked themselves. But only the side air bags went off - the frontal ones didn't.
 

20IndigoBlue02

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TriDubInventory said:
I have a relative that is an insurance adjustor, and she was asking me a question about the VW's. She stated that she has a client that is saying that VW has a engine kill switch after a accident, to prevent engine fires.

So she was asking me if I had heard of that in my Jetta. This is the first that I had heard of something like that, and wasn't even sure if that was truth. But according to this person she was tallking to, she stated that all newer VW's have these. The VW in question is a 2005 Jetta, and not sure what type of motor they have, but I did ask.

Truth, or wool over the eyes?
...if it does, apparently mine wasn't working. After I woke up from the crash, I had to turn off the car myself, after hearing the low coolant buzzer go on.
 

oilhammer

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There are just too many to list....
FLMan said:
Why didn't the 98 TDI shut down after multiple flipping?
Because the A3 cars and presumably every VE diesel does not have the circuit from the SRS module to the fuel pump relay. Notice I said "modern" cars...the A3 design, dating back to 1993, is hardly what I would call modern. It is barely more than a warmed-over A2, dating back to 1985!

I know for certain the 2002 2.0L Jetta does, because I had some kid fry his SRS ECU while wiring up his own stereo system and the car will not run without that input. The power-up leg of the fuel pump relay goes through the SRS module.

Diesel is not nearly as volatile in a crash as gasoline is.
 

vzdude

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98 Jetta TDI
concours said:
ALL fuel injected gas engined vehicles REGARDLESS of brand, have a federally mandated inertia switch to prevent fuel from being pumped at an accident scene after broken lines. The conventional diesel engines fuel pump is mechanically driven and is inherintly safe. The PD engine's electric lift pump must also have an inertia switch built in to it's circuit.
I have to respectfully disagree. I work on numerous brands of vehicles every week, and very few of them have an actual inertia switch. There is absolutely nothing mandated by the federal government on the issue as well. I've been wrong before, but I'd bet my next paycheck on this one! What they DO require is a rollover valve which simply blocks the vent on the tank. Doesn't work real well, and if there is a hole in the tank it's useless. Here is just one example of a vehicle that I can guarantee doesn't have an inertia switch.


OPERATION

All models pass a full 360 degree rollover test without fuel leakage. To accomplish this, fuel and vapor flow controls are required for all fuel tank connections.
Two check (control) valves are mounted into the top of the fuel tank. Refer to Fuel Tank Check Valve for additional information.
An evaporation control system is connected to the fuel tank to reduce emissions of fuel vapors into the atmosphere. When fuel evaporates from the fuel tank, vapors pass through vent hoses or tubes to a charcoal canister where they are temporarily held. When the engine is running, the vapors are drawn into the intake manifold. Certain models are also equipped with a self-diagnosing system using a Leak Detection Pump (LDP) or NVLD Pump, and/or an On-Board Refueling Vapor Recovery (ORVR) system. Refer to Emission Control System for additional information.
 

concours

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vzdude said:
I have to respectfully disagree. I work on numerous brands of vehicles every week, and very few of them have an actual inertia switch. There is absolutely nothing mandated by the federal government on the issue as well. I've been wrong before, but I'd bet my next paycheck on this one! What they DO require is a rollover valve which simply blocks the vent on the tank. Doesn't work real well, and if there is a hole in the tank it's useless. Here is just one example of a vehicle that I can guarantee doesn't have an inertia switch.


OPERATION

All models pass a full 360 degree rollover test without fuel leakage. To accomplish this, fuel and vapor flow controls are required for all fuel tank connections.
Two check (control) valves are mounted into the top of the fuel tank. Refer to Fuel Tank Check Valve for additional information.
An evaporation control system is connected to the fuel tank to reduce emissions of fuel vapors into the atmosphere. When fuel evaporates from the fuel tank, vapors pass through vent hoses or tubes to a charcoal canister where they are temporarily held. When the engine is running, the vapors are drawn into the intake manifold. Certain models are also equipped with a self-diagnosing system using a Leak Detection Pump (LDP) or NVLD Pump, and/or an On-Board Refueling Vapor Recovery (ORVR) system. Refer to Emission Control System for additional information.
That's fine... you won't hurt my feelings. :p The verbiage you pasted above is an abstract description of a fuel system design, nothing more. Ford was the first domestic OEM to have inertia switches and manual resets in the trunk, before it was commonplace. Think about the thousands of accidents that happen every day, engines are mashed, displaced, fuel lines torn. :eek: How many wrecks are there with 15 gallons of gas pumped onto the ground??? NONE... because the switches are there.

Please share with us how you know the following statement you made to be true... we'd like to know.:D
"There is absolutely nothing mandated by the federal government on the issue as well"

I just checked the four factory service manuals I had here, 2001 Full size GM P/U's and SUV, 2001 Jeep Grand Cherokee, 1998 Taurus, 2000 Impala, all schematics show inertia switch. I remember diagnosing and fixing a faulty inertia switch on my Nephew's '86 Monte Carlo 4.3TBI.

I stand with my initial statement. :cool:
 
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vzdude

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concours said:
That's fine... you won't hurt my feelings. :p The verbiage you pasted above is an abstract description of a fuel system design, nothing more. Ford was the first domestic OEM to have inertia switches and manual resets in the trunk, before it was commonplace. Think about the thousands of accidents that happen every day, engines are mashed, displaced, fuel lines torn. :eek: How many wrecks are there with 15 gallons of gas pumped onto the ground??? NONE... because the switches are there.

Please share with us how you know the following statement you made to be true... we'd like to know.:D
"There is absolutely nothing mandated by the federal government on the issue as well"

I just checked the four factory service manuals I had here, 2001 Full size GM P/U's and SUV, 2001 Jeep Grand Cherokee, 1998 Taurus, 2000 Impala, all schematics show inertia switch. I remember diagnosing and fixing a faulty inertia switch on my Nephew's '86 Monte Carlo 4.3TBI.

I stand with my initial statement. :cool:
O.K.....here are some FACTORY wiring diagrams for the 2001 Jeep Grand Cherokee you referenced , just for 1 example. I have access to ALL Chrysler products online, so these are easiest for me to reference. This is only to disprove the blanket statement about ALL vehicles having an inertia switch. The Jeep uses an ASD ( Auto Shut Down) relay that you may have mistaken for an inertia device. The ASD relay uses an input from the PCM to energize the coil and fuel pump, but no actual inertia switch either. IIRC as well, the 01 Chevy pickups use the oil pressure sensor to kick the fuel pump relay off if it loses oil pressure. No actual inertia switch.

http://pics.tdiclub.com/showgallery.php?cat=4000&page=0&sort=
 

compu_85

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On the A2 VWs the fuel pump relay has an RPM input. When the motor stops the relay will shut off, close for just a moment, then shut off again.

-Jason
 

vzdude

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Here is another example.....lots of reading, but just Ctrl-F and search for inertia.....here's a couple of examples.

Volkswagen of America, Inc. (VW) was concerned with potential reliability problems associated with inertia-activated fuel cut-off switches. VW explained that it was using an engine rotation sensing device for cutting-off fuel flow in its vehicles. VW also stated that additional fuel tank filler valve systems were unnecessary. In addition, VW recommended that we refer to ECE Regulation No. 34 for possible component test requirements, but did not specify particular tests.


Chrysler Corporation (Chrysler) argued that fuel system integrity should be evaluated as a system and expressed its opposition to any initiative to introduce component design or performance requirements into Standard No. 301. Chrysler explained that it used a fuel shut-off device that senses engine rotation for stopping the fuel flow and stated that additional protection had not been shown to be any more effective in reducing fuel related fires. Chrysler stated that it was premature to consider using an electrical power shut-off device for reducing fuel induced fires. Chrysler argued that more research is needed to verify that the proposed mitigation approach will not harm other systems that are critical to occupant protection, during and after the crash event. Chrysler opposed the concept of using fire extinguishers and fire retardant systems for engine compartment fires and stated that the ignition of a vehicle fire does not necessarily occur at a predictable point in time during a vehicle crash. In addition, Chrysler stated that, in some fires, a "second ignition" is encountered that would not be mitigated by these proposed systems.

Volvo Cars of North America, Inc. (Volvo) stated that shutting off fuel flow quickly during and after a crash could help to reduce the risk of engine fires and the spread of fires once one had started. Volvo stated that since a number of methods could be employed to stop the flow of fuel, there should be no requirement mandating certain equipment. Volvo stated that we should give manufacturers the freedom to design their own systems by specifying performance criteria for them to meet. Volvo suggested that we incorporate the plastic fuel tank test requirements of ECE Reg. No. 34 into Standard No. 301.

AND FINALLY...........The proof!.........
Based on the foregoing, we have decided not to pursue rulemaking with respect to fuel system component performance at this time. Our own review of NASS data did not reveal a significant difference in the rate or severity of post crash fire occurrence in vehicles with and vehicles without inertia activated fuel pump shut-off devices. GM crash test data support this conclusion. GM monitored the fuel pump circuitry in all of the crash tests that it conducted for its above-mentioned research. All of the crashes caused electrical circuitry shorting that disabled the fuel pump before the inertia switch could be activated.
 

concours

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vzdude said:
O.K.....here are some FACTORY wiring diagrams for the 2001 Jeep Grand Cherokee you referenced , just for 1 example. I have access to ALL Chrysler products online, so these are easiest for me to reference. This is only to disprove the blanket statement about ALL vehicles having an inertia switch. The Jeep uses an ASD ( Auto Shut Down) relay that you may have mistaken for an inertia device. The ASD relay uses an input from the PCM to energize the coil and fuel pump, but no actual inertia switch either. IIRC as well, the 01 Chevy pickups use the oil pressure sensor to kick the fuel pump relay off if it loses oil pressure. No actual inertia switch.

http://pics.tdiclub.com/showgallery.php?cat=4000&page=0&sort=
Soooooo.... you feel that all the manufacturers interupting the fuel pump in the event of a crash is just a coincidence? They are all just "good corporate citizens"? Sorry, they must made (in most cases) to do the right thing. I stand by my claim.

When I said "Inertia switch" I refer to some way to shut off the fuel after a frontal impact. Whether the SRS signal is monitored and used, the GM oil pressure switch thing was back in the TBI days, now the ECM turns on the fuel pump relay with an output, the ECM's programmed logic to turn that off may be based on the condition(s) of the signal(s) coming from crank sensor, cam sensor, both, oil pressure, SRS G forces sensed or whatever the resident wizards chose to accomplish the task. Same result.

"Factory" manuals... Alldata? JC I cited the four paper HELM books I had laying around.
 

vzdude

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Well......they are not "INERTIA SWITCHES" as in the statement that you claimed. Yes....they do shut off the fuel pump, but by other means than the typical "Ford" style inertia switches. My factory manuals are accessed via Dodge's Dealerconnect website. And yes, I have access to Alldata as well. Everything Alldata has is copied from factory service manuals as well. I just call a spade a spade, when I see it. You know, tomatoe vs. tomato. Again.....nothing personal, just want everyone to be informed. I'm no VW expert, but I'm working on it. I'm an admitted newbie to the TDI world, but have been a Master Certified A.S.E. Tech since 1994 and a Dodge Bronze and Silver Certified Tech since 2000.
 

concours

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vzdude said:
Here is another example.....lots of reading, but just Ctrl-F and search for inertia.....here's a couple of examples.

Volkswagen of America, Inc. (VW) was concerned with potential reliability problems associated with inertia-activated fuel cut-off switches. VW explained that it was using an engine rotation sensing device for cutting-off fuel flow in its vehicles. VW also stated that additional fuel tank filler valve systems were unnecessary. In addition, VW recommended that we refer to ECE Regulation No. 34 for possible component test requirements, but did not specify particular tests.


Chrysler Corporation (Chrysler) argued that fuel system integrity should be evaluated as a system and expressed its opposition to any initiative to introduce component design or performance requirements into Standard No. 301. Chrysler explained that it used a fuel shut-off device that senses engine rotation for stopping the fuel flow and stated that additional protection had not been shown to be any more effective in reducing fuel related fires. Chrysler stated that it was premature to consider using an electrical power shut-off device for reducing fuel induced fires. Chrysler argued that more research is needed to verify that the proposed mitigation approach will not harm other systems that are critical to occupant protection, during and after the crash event. Chrysler opposed the concept of using fire extinguishers and fire retardant systems for engine compartment fires and stated that the ignition of a vehicle fire does not necessarily occur at a predictable point in time during a vehicle crash. In addition, Chrysler stated that, in some fires, a "second ignition" is encountered that would not be mitigated by these proposed systems.

Volvo Cars of North America, Inc. (Volvo) stated that shutting off fuel flow quickly during and after a crash could help to reduce the risk of engine fires and the spread of fires once one had started. Volvo stated that since a number of methods could be employed to stop the flow of fuel, there should be no requirement mandating certain equipment. Volvo stated that we should give manufacturers the freedom to design their own systems by specifying performance criteria for them to meet. Volvo suggested that we incorporate the plastic fuel tank test requirements of ECE Reg. No. 34 into Standard No. 301.

AND FINALLY...........The proof!.........
Based on the foregoing, we have decided not to pursue rulemaking with respect to fuel system component performance at this time. Our own review of NASS data did not reveal a significant difference in the rate or severity of post crash fire occurrence in vehicles with and vehicles without inertia activated fuel pump shut-off devices. GM crash test data support this conclusion. GM monitored the fuel pump circuitry in all of the crash tests that it conducted for its above-mentioned research. All of the crashes caused electrical circuitry shorting that disabled the fuel pump before the inertia switch could be activated.
The last sentence is laughable.... that is the most illogical conclusion that could be drawn. I'd not be so willing to bet not becoming a human BBQ that the right wires were damaged and shorted to save lives.

"All of the crashes caused electrical circuitry shorting that disabled the fuel pump before the inertia switch could be activated."

Sounds like your "proof" is merely a transcript of a hearing...

So you claim there is no law requiring the fuel pump to be shut off in a severe frontal impact??? We all bank our families lives that the wire harness to the engine is going to be damaged and the current limiting devices sense the short circuit and respond as designed? Ludicrous.
__________________
 

oilhammer

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There are just too many to list....
Modern GM cars use a similar system as Volkswagen. Ford has gone away from the old 'inertia' switches in many newer models, too. That was kind of '80s technology, anyways.

Essentially, if the car has full CAN, the need for such simplistic mechanical/electrical devices is not needed. The ECUs communicate on a stupid-fast baud rate on the CAN bus, and at the same time the signal is being sent to deploy any airbags and fire any seat belt pretensioners, the signal is also being sent to the rest of the ECUs that would require this information...this all happens much faster than any human could think.

Ford has tapped into Volvo's extensive safety R&D as of late, since Ford owns Volvo. Cars like the Five Hundred and Freestyle (once again a Taurus and Taurus X, respectively) are based on a Volvo platform, and the current Euro Focus, Volvo S/V40, and Mazda 3 are also on a shared platform that was jointly developed with Volvo on Ford of Europe. All of this means the Swedes likely laughed at a mere inertia switch. So, throwback models like the Ranger will still have them for the time being, but the Five Hundred likely does not. Why have an inertia switch when a crash sensor is far more accurate and is already needed for SRS use?

Toyota also links the SRS ECU (via CAN, of course) to any and all high-voltage controllers that the hybrids as well as the electric-steered cars use. Again, to safely and instantaneously isolate any high voltage to the batteries in the event of an accident. If a Prius is in a wreck hard enough to deploy the airbags, the main current relay from the main battery bank will NOT be allowed to power up. And if you interrogate the engine/hybrid ECU, you will see the DTC stored for such.

The complexity of modern cars' CAN and multiplexing systems are far more complex than many realize. At Toyota school we counted 16 different things that happened to the LS430 with Smartkey when you simply walked near the car with the key in your pocket! And you could monitor the CAN bus when this happens and actually watch the graphing of the interchange between all the ECUs, but we had to record it and slow it down so we could even see it....it happens that fast. :eek:
 

mrGutWrench

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concours said:
(snip) So you claim there is no law requiring the fuel pump to be shut off in a severe frontal impact??? We all bank our families lives that the wire harness to the engine is going to be damaged and the current limiting devices sense the short circuit and respond as designed? Ludicrous.
__________________
__. Hey, CC. The best rule is "when you're only getting deeper, quit digging"! :D

__. You said that Federal laws require an inertial switch. Please read/search/whatever:
http://a257.g.akamaitech.net/7/257/2422/16nov20071500/edocket.access.gpo.gov/cfr_2007/octqtr/49cfr571.301.htm
and let us know where you find that. (I have a time-saver for you, you won't).

__. The standard says that the vehicle must not leak fuel. It doesn't say anything about fuel pumps or fuel pressure or fuel lines or electrical systems or anything. But your statement about inertial switches is just FLAT OUT WRONG.
 
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