Electrical !?!

[nick02]

Hello, '02 Jetta. New Alternator 10/21. Replaced (warranty 3/22). What is happening is When cold, start- ABS blinking, headlights dimming, & radio lights out during glow plug cycle. Once glow plug cycle complete, lights work well and appears normal. Yesterday, warmed up, start- 3-beeps, and ABS. Starter replaced last year (original), & battery (6yrs old). All grounds cleaned at that time. I completed 5 sp swap 5/13. Everything has worked well until 10/21. Any ideas on where to look? Thank-you, Nick

 

[oilhammer]

I'd start by doing some OBD checks, then some voltage drop tests, both power and ground, starting at the battery.

 

[dieselnewbie]

I’ve had similar issues that I finally traced back to a faulty connection at the battery fuse box. The big red wire was loose at the crimp connection and wiggled while cranking, which resulted in craziness going on in my instrument cluster. Could have possibly re-crimped the connection, but actually had a new fuse box assembly on a shelf.

 

[BobnOH]

6 year old battery? I've never had a battery last much longer that the year rating. 50 years driving, of course I'm not meticulous with yearly battery maintenance.

 

[nick02]

I will look at that cable. I am going to connect the Vag Com too. Thank-you for the suggestions. Yep, 6 year battery. I don't drive this as much any more. AC is out so once it gets into the 80's it sits. The foam blew out of the blend door a few years so it sits when it gets to low 30's. Nick

 

[BobnOH]

Easy enough to have the battery load tested or do it the old school way if you have a proper hydrometer.

 

[Nero Morg]

6 year old battery? I've never had a battery last much longer that the year rating. 50 years driving, of course I'm not meticulous with yearly battery maintenance.

I have a pair of duralasts in my truck that have been in there since 2010, still running strong.

Most auto parts stores will load test a battery for free and even print out a health receipt for it.

 

[nick02]

Checked yesterday with Vag-com, only code was ABS 00668. Found post from 2018 to look at fuse 9, 5 amp. The posts were dark but fuse ok. Wire brushed it and cleared code. This morning, 38 degrees ABS flashing, lights dim. Got to work, turned off lights and car. Parking/turn signals lit. Had to start car, cycle headlight switch a few times- lights off. Also, my trip zeroed & clock changed time. Nick

 

[Nero Morg]

Go get your battery tested. Trip and clock zeroing out during cranking is an indicator of voltage loss

 

[irvingj]

You might also have a look at your battery cables. I've been having slow crank/slow start issues for a while. Battery's old (8yrs) so I figured that's what it was -- and that may still prove to be true-- but then I noticed some corrosion in the copper strands of the negative cable. If you look at the end of it, where the battery connector is molded onto the copper wire, you can see the cut ends of all those strands.

Mine had visible corrosion discoloration there. Stripping back the insulation, I found it went back into the cable at least 2-1/2". Last week I changed both cables (positive cable was in similar condition) and so far it seems to both crank and start faster. This is on a 2005 BEW wagon with about 162K on the clock. Both cables came to about $225 from idParts.

 

[Tdijarhead]

Dying battery or bad battery connections.

 

[nick02]

Today...45 degrees. 12.5 , cycle GP's volts drop 11.6, start volts drop to 10.5, starts- volts up to 13.9-14.2. Drove 50 miles 4 stops, not one problem. Is there a test for the ignition switch?

 

[Nuje]

6 year old battery? I've never had a battery last much longer that the year rating. 50 years driving, of course I'm not meticulous with yearly battery maintenance.

Friend of mine had her car suddenly not able to start and wouldn't hold a charge. Took it to dealer, and they diagnosed bad battery.
It was ORIGINAL....on her 2006??!!! All the techs had to come out and take a look.

 

[nick02]

This morning, drove to work, parked shut off car. Pushed window switch to roll up window. Something clicked then flashers started, all dash lights blinking, clock changed, trip zeroed. I had to turn key to on then it all went to normal. I was able roll down the windows. Could this be my ignition switch shorting out? Nick

 

[Tdijarhead]

Today...45 degrees. 12.5 , cycle GP's volts drop 11.6, start volts drop to 10.5, starts- volts up to 13.9-14.2. Drove 50 miles 4 stops, not one problem. Is there a test for the ignition switch?

13.9-14.2 means your alternator is working. 12.5 is good but glowing it shouldn’t drain it to 11.6, you need to replace your 6 year old battery. Your glow plugs at 45* should have been on and right off, barely using any charge, unless you extended the glow time with vcds.

 

[nick02]

Battery replaced October same time as alternator. This morning it was 51 degrees. It is going to be hot and sunny today so I am going to remove my cowl and look at the GP relay. Glow plug light out quick, I don't think it even spins a full revolution and it fires right up. It is after that the fun starts.

 

[Mozambiquer]

Battery replaced October same time as alternator. This morning it was 51 degrees. It is going to be hot and sunny today so I am going to remove my cowl and look at the GP relay. Glow plug light out quick, I don't think it even spins a full revolution and it fires right up. It is after that the fun starts.

What brand alternator? How's the wiring? Did you check the ground connections? Check the fuse box on top of the battery as well.

 

[Tdijarhead]

Battery replaced October same time as alternator. This morning it was 51 degrees. It is going to be hot and sunny today so I am going to remove my cowl and look at the GP relay. Glow plug light out quick, I don't think it even spins a full revolution and it fires right up. It is after that the fun starts.

Misunderstood the battery replacement bit. Check your connections and battery top fuse block as Mozambiquer suggests.

 

[nick02]

Battery tray removed, grounds wire brushed and di electric grease, all fuses on top removed cleaned and di electric greased. I did the timing belt, 3rd, and oil pump in Feb. Cleaned ground cable, positive cable. Since owning this car, I have always been able to roll up/down windows after car was turned off. Recently, once in a while as soon as I turn it off and push the window switch, it goes nuts. Had to turn key back to run as it reset itself.

 

[muzy]

A oldie but, how's the 109 and all the relays in that area? You may have one partly smoked.

 

[Tdijarhead]

If the glow plug light comes on for even a second or two the 109 should be ok.

Battery tray removed, grounds wire brushed and di electric grease, all fuses on top removed cleaned and di electric greased. I did the timing belt, 3rd, and oil pump in Feb. Cleaned ground cable, positive cable. Since owning this car, I have always been able to roll up/down windows after car was turned off. Recently, once in a while as soon as I turn it off and push the window switch, it goes nuts. Had to turn key back to run as it reset itself.

Did this help?

To your question about a failing ignition switch, if your e-brake is on and you turn the ignition to on does your headlights, radio, wipers, and heater fan work? Anything that is powered when the ignition is turned to on should work if multiple systems do not work then the ignition is suspect.

 

[irvingj]

FWIW: I had removed my battery & tray some time ago and cleaned up all 3 grounds down there, but still had slow cranking issues. Thought it was the battery, which is in fact old... But then I looked closely at the ends of the battery cables and saw green corrosion among the strands at the terminals. Stripped back some insulation, and sure enough corrosion extended back into the cable an inch or two.

Replaced both pos and neg battery cables and things improved tremendously. Something to look at. (This on a 2005 BEW wagon with 163K on the clock.)

 

[nick02]

Running around yesterday, key fob would only unlock driver door. Checked battery, 3.1 volts.

 

[nick02]

I pulled all the fuses out. Checked each with a meter. The blades on the larger fuses were clean, the blades on most of the smaller fuses were covered in tarnish. Wires brushed them and installed. What causes the discoloration? I have never seen that before. Nick

 

[Nuje]

I always assumed it was just oxidation / corrosion.
Lots of my fuses are "dirty", too - never fixed a problem by cleaning one up, though; always had to track down a component or wiring issue elsewhere.

 

[mittzlepick]

Fuses coated with tin tarnishes like silver, maybe original factory fuses have some silver in the coating unlike crap of the shelf now. That why i strip em all out before i s rap a car

 

[nick02]

So far, all fuses pulled, cleaned tested, ignition switch pulled blades clean, all relays under dash pulled no burns. GP relay pulled clean, grounds under battery clean. Any other areas I need to be looking at for possible shorts? Nick

 

[nick02]

Today started fine, 80 degrees. 100 yards, ABS & Brake light blinking, 3 beeps. Stalls, starts right back up, not a problem the rest of the drive home. Completed auto-scan, Address 46 Central Convenience 7 Faults:
00849 S-contact at ignition
01331 Door control module driver 52-10 voltage too high
01332 Door control module passenger 52-10 voltage too high
01333 Door control module rear left 52-10 voltage too high
01334 Door control module rear right 52-10 voltage too high
00935 Electric window motor 62-10 incorrect adjustment
00931 locking module for central locking rear right 27-10 implausible signal
Address 03 ABS Brakes 00668 supply voltage terminal 008 implausible signal 008.

 

[wonneber]

The high voltage could be a bad ground.
With the car running, head lights on measure the voltage from the battery post (not the terminal) to the battery terminal, then to the ground at the trans, then the case of the alternator.
I would not want to see more than a few tenths of a volt.
Next same test through the positive cable.
Did you measure the battery voltage?

 

[nick02]

Not following. Measure from Pos post to neg clamp, trans ground, then alt case? Nick