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DISCUSSION => Electrical => Topic started by: DRtothE on August 10, 2008, 05:56:16 AM

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 10, 2008, 05:56:16 AM

Temp gauge is working, Speedometer is working, just the Tech and MPG meter have gone out. I'm sorry if this is a much asked question, but i tried to search this forum with no luck in finding a solution. Any ideas?

Andre O.

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 10, 2008, 02:32:16 PM

not one reply today yet?? wow, i'm going to check fuse #21 after work, but i was sure that 21 controlled the Tach, MPG, AND temp, and like i said, my temp is working. thanks for reading.

Title: Tachometer / MPG malfunction
Post by: AcSchnitzer318is on August 10, 2008, 04:09:37 PM

I had this problem with a bad SI board battery set.  Resoldered on new batteries and all is right with the world again.

Title: Tachometer / MPG malfunction
Post by: Jimmy Lewis on August 10, 2008, 07:49:09 PM

So the SI batteries being bad can still allow some of the gauges to work?

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 11, 2008, 02:40:27 AM

i was running on a car without an alternator, talk about dedication while being broke, i bought a battery charger for 30 bucks, and besides having to buy another battery, i've been dead on the side of the road countless times, calling friends and fam to give me a lift.

i've replaced the alternator since, but do you think this could be the cause of the SI board batt.s dying

P.S. my temp gauge still works well

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 16, 2008, 01:37:03 AM

and nothing, thanks a heap

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 29, 2008, 12:01:04 AM

i know the answer is on here somewhere, i just can't find it

Title: Tachometer / MPG malfunction
Post by: AcSchnitzer318is on August 29, 2008, 12:33:45 AM

Have u tried the si board batts yet?  The si board batts will affect your Tach/MPG/Service interval lights.  Speedo get signal from sensor in diff, and fuel... well from the sensor in the tank, duh.  So, yes some gauges will work with a bad set of batts.

Title: Tachometer / MPG malfunction
Post by: DRtothE on August 29, 2008, 11:16:00 PM

thx schnit

Title: Tachometer / MPG malfunction
Post by: SnPaC on November 04, 2008, 03:34:10 PM

Quote from: AcSchnitzer318is;55696

Have u tried the si board batts yet?  The si board batts will affect your Tach/MPG/Service interval lights.  Speedo get signal from sensor in diff, and fuel... well from the sensor in the tank, duh.  So, yes some gauges will work with a bad set of batts.

While driving to work this AM, stopped the car to get gas. When i restarted...no fuel gauge, tach or temp. Just like that! Do they normally fail like that? I was low on fuel and the fuel light was on for most of  the drive ~1/2 hr. Might this have drained that SI batts? Before I tear this thing apart, does anyone know if I have the old or new board?
It is a VDO cluster and noticed another unusual occurrence. When i start the car up. both the tach and economy gauge momentarily move then die. With this, i am hesitant to think it is a fuse. Also, not all of my idiot lights light up when i turn on the ignition as they have in the past; only the anti-lock & battery illuminate, and the brake lining light illuminates only when the starter is cranking.

Unfortunately, I've not paid much attention in the past to which come on, but i think it is all of them when I turn the ignition on...

Perhaps this is just a coincidence, but losing all the gauges except for the speedo at once?????  Strange