Revised B4 MFA conversion article

[RIP TDI]

Cluster identification is easier than that, cluster installed or out: '95 and earlier has 2 visible screw heads securing the speedo face and the speedo starts at 10 MPH, '96/'97 have no screws and the speedo starts at 0 MPH.

 

[G60ING]

Cluster identification is easier than that, cluster installed or out: '95 and earlier has 2 visible screw heads securing the speedo face and the speedo starts at 10 MPH, '96/'97 have no screws and the speedo starts at 0 MPH.

I like that speedo MPH differnace.

 

[dieseljunkie]

I like that speedo MPH differnace.

I currently have a 96 Passat 5spd VR6 cluster to replace the dead cluster from my Passat TDI. In test drive with a GPS, the speedo is almost identical. The odo showed a 0.1 mile difference in a 10 mile drive. The tach is reading very low. Where is the sensor for the tach in the Passat TDI and in the VR6 5 spd gasser?

 

[G60ING]

I currently have a 96 Passat 5spd VR6 cluster to replace the dead cluster from my Passat TDI. In test drive with a GPS, the speedo is almost identical. The odo showed a 0.1 mile difference in a 10 mile drive. The tach is reading very low. Where is the sensor for the tach in the Passat TDI and in the VR6 5 spd gasser?

you need to follow the instructions at the beginning of this thread. There are instructions that explain what tach pulse signal convertor to use.

 

[RIP TDI]

I like that speedo MPH differnace.

Hence the expression, "That GLX looks fast just sitting still"

 

[dieseljunkie]

you need to follow the instructions at the beginning of this thread. There are instructions that explain what tach pulse signal convertor to use.

I have read the first post in this thread where the pulse freq adapter was mentioned as one way to correct the tach reading. However, I did not find any mention of where the tach signal actually originates from. I know Chris did a lot of work on the writeup and I have no doubt his instructions are correct. But I like to understand how things work rather than just following a set of instructions.

 

[dieseljunkie]

I found this rpm sensor for the 96-97 VR6 Passat. Also known as Engine speed sensor or crankshaft position sensor.

http://www.germanautoparts.com/Volkswagen/Passat/EngineElectrical/182/3

I did not find a RPM sensor for the Passat TDI listed though. So what signal is driving the VR6 cluster's tach in my Passat TDI? Why is it reading low? Anyone???

 

[G60ING]

I found this rpm sensor for the 96-97 VR6 Passat. Also known as Engine speed sensor or crankshaft position sensor.

http://www.germanautoparts.com/Volkswagen/Passat/EngineElectrical/182/3

I did not find a RPM sensor for the Passat TDI listed though. So what signal is driving the VR6 cluster's tach in my Passat TDI? Why is it reading low? Anyone???

I don't know what the drive is on a TDI. It could be the crank position sensor or the 3rd injector but I know that 4 cylinder tachs will only read correctly with 4 cylinder cars and the same with 3,5,6 cylinders. If you swapped in a 4 cylinder gasser cluster you would be fine.

 

[dieseljunkie]

I don't know what the drive is on a TDI. It could be the crank position sensor or the 3rd injector but I know that 4 cylinder tachs will only read correctly with 4 cylinder cars and the same with 3,5,6 cylinders. If you swapped in a 4 cylinder gasser cluster you would be fine.

Anyone know where the tach signal originates from in the Passat TDI? Inquiring mind wants to know.

 

[RIP TDI]

The RPM sensor in the lower block drives the tach, via the ECM. A second RPM signal from the "W" terminal on the alternator is used by the ECM.

 

[dieseljunkie]

The RPM sensor in the lower block drives the tach, via the ECM. A second RPM signal from the "W" terminal on the alternator is used by the ECM.

Lower block? Where exactly? Is it a one per rev signal?

 

[RIP TDI]

Forget the RPM sensor; the TDI and VR6 sensors have the same pulse rate per cylinder (thus the 33% lower tach reading for a GLX cluster in a TDI).

If you're looking for a no cost alternative to installing the pulse frequency adaptor, there actually is one which I included in previous versions of the conversion article but removed for the current revision.

When I originally did the conversion 10 years ago, there wasn't at that time a robust, versatile-input signal interface with enough adjustability on the market and so I made a graphic overlay for the tach face. It rendered the tach accurate, but had a narrower sweep that was a bit harder to read at a glance. Its a bitmap file that you can print out on an adhesive-backed mailing label and install easily. I can email it to you if you're interested.

 

[dieseljunkie]

Please send the bitmap file. I'll be pm'ing you.

 

[jonhohlf]

Chris,

I see the instructions for this are currently unavailable? I need to do this for my sister's B4V GLX TDI, I could copy what I had done for mine (but that would involve removing my additional teardown of my working cluster, and it would be much easier to just follow the instructions as they were posted). I have the Dakota Digital converter and will be using an old TDI cluster for parts and have all the resistors that I will need leftover from when I did my conversion.

Any help would be greatly appreciated.

Jon

 

[RIP TDI]

I'm sorry and embarassed to say that I accidently deleted the article and never backed it up, so unless there's some way to recover it, its gone and won't be replaced

 

[compu_85]

What was the URL?

-Jason

 

[jonhohlf]

I'm sorry and embarassed to say that I accidently deleted the article and never backed it up, so unless there's some way to recover it, its gone and won't be replaced

Chris, Check out this link:

http://web.archive.org/web/20080801060652/http://forums.tdiclub.com/showthread.php?t=101455

Should help to get it back up. I also copied it to a Word document from there, if you need that.

Jon

 

[ninedee_golf_tdi]

I must be doing something incorrectly here. I have a 96 glx chassis and the original glx cluster. I added the two resistors, the led lamp in position 5 and the wire for the mil light. Key on and the new mil lamp glows very faintly, but it does turn on. Put a tdi cluster in and all bulbs work as they should. So.... either the resistor(s) is causing too much voltage drop, or, the resistors are unnecessary to begin with in this application, or the 276-021 3vdc Radio Shack led is too high of a voltage rating ? Any thoughts ? Thanks.

 

[dieseljunkie]

I must be doing something incorrectly here. I have a 96 glx chassis and the original glx cluster. I added the two resistors, the led lamp in position 5 and the wire for the mil light. Key on and the new mil lamp glows very faintly, but it does turn on. Put a tdi cluster in and all bulbs work as they should. So.... either the resistor(s) is causing too much voltage drop, or, the resistors are unnecessary to begin with in this application, or the 276-021 3vdc Radio Shack led is too high of a voltage rating ? Any thoughts ? Thanks.

If it lit dimly, you have the polarity correct so it comes down to the spec of the Radio Shack LED. You can try lowering the resistor value and thus drive it with more current. Can you steal a LED from a cluster and replace the Radio Shack LED?

 

[ninedee_golf_tdi]

I must be doing something incorrectly here..

I knew the answer was one of the three variables I mentioned, too much voltage drop, incorrect resistor application, wrong bulb. I just now figured out I grabbed the wrong resistor out of the bag of 1,000. I grabbed an 82k resistor instead of 820. Guess the old eyeballs need a tuneup. Correct color code is grey red brown. You should not make the legs of the resistors as long as they might hit the tach face upon reassembly.

 

[G60ING]

When i was at the JY today I noticed that the european B4 gasser cluster did not say unleaded fuel only on it and niether do any of the other B4 clusters that i've seen on ebay.de today. I may have to keep and eye out for a vr6 cluster on ebay.co.uk

 

[RIP TDI]

You don't want a UK or Euro cluster. MFA fuel consumption is measured in Imp. gallons or liters and you can't change the calculated units. Also, I believe neither is equipped with an MIL from the factory. Whether its missing an LED, cluster circuit or the ECU doesn't provide a signal, I don't know but getting a functioning MIL might take some work.

 

[G60ING]

I Oh sorry about that. I plan to use just the fuel gauge face and the metric units for water temp or fuel capcity don't bother me. I think the sticker might bother me.

 

[RIP TDI]

Unless the flat black of the sticker is a really close match with the gauge face, I think it is objectionable. The ones on my two are darn close to undectable under most lighting conditions.

While I haven't tried it, a sticker with "TDI" in factory font with a nice contrast between font and background color (maybe silver over black or red over silver) might actually be an improvement over a plain face.

 

[G60ING]

Any chance somebody has a spare sticker? I'll give it a shot to help save some $$

 

[jollyGreenGiant]

I'll get a picture up but IMO the best bang for the buck in terms of dealing with the Unleaded Fuel Only deal is using a label maker with white label stock and black lettering. I printed "DIESEL FUEL ONLY" and then trimmed it slightly. It covers the existing text perfect and the contrast of white and black looks really nice, kinda looks like the A2 style clusters with the contrasting black and white where the upshift indicator is...

 

[ninedee_golf_tdi]

Another Glitch with U1/6 (Tach Signal)

I spliced U1/6 into the Dakota Tach Adapter. When I started the engine I lost my oil pressure signal causing the dash red indicator light to flash continuously, and the tach did not work. I reconnected both ends of the cut U1/6 wires and the oil pressure lamp extinguished. I pulled U1 out of the relay panel to ensure I had the right connector and wire and it was correct. I pulled U2 out of the relay panel, and U2/6 is empty so no chance of goofing that up. Any ideas where the tach signal wire is ? Thanks.

 

[RIP TDI]

Tach signal is U1/6, no exceptions.

U1 and U2 plugs are blue. You're either using the G1 or G2 plugs which are white, or you've got the wrong pin in the U1 plug. The 2 oil pressure signals run through U1/3 and U1/5 (and G2/10 & G2/11).

 

[ninedee_golf_tdi]

The harness looked to be unmolested in the donor car so I think I can rule out someone put the wrong wire in the wrong hole but that might be the case. Here is the harness connector and the wire for my U1/6:

 

[RIP TDI]

Did you forget to lock down all the relay panel connectors with the lock bar?