Tachometer Problem
Thread Starter
Instructor
Joined: Jun 2006
Posts: 241
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From: Gambrills Maryland
Tachometer Problem
Yesterday morning when I drove my car my tach was stuck at around 3,400 rpms. I drove it later in the day and the tach was fine. Last night it was doing the 3,400 rpm thing again. What gives?
Thread Starter
Instructor
Joined: Jun 2006
Posts: 241
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From: Gambrills Maryland
Safety Car
Joined: Nov 2002
Posts: 4,394
Likes: 6
From: Melbourne FL
If the needle does not appear to be physical hung on something, I would bet the gauge itself is going bad since the HUD records correctly.
Thread Starter
Instructor
Joined: Jun 2006
Posts: 241
Likes: 0
From: Gambrills Maryland
A week later it is still happening. Not throwing any DIC codes for it. After holding reset for awhile it will now rest on 0 while driving. What part would I need to replace with these symptoms?
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Instructor
Joined: Jul 2007
Posts: 174
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From: Toronto Ontario
Helm's manual time!
I think It's time to get a helm's manual for your vette. It could be a simple wiring problem. There are a lot of troubleshooting tips in the manual to help you pinpoint the problem you are having with your gauge cluster. Great investment.
Drifting
Joined: Oct 2004
Posts: 1,384
Likes: 8
From: Southwest Virginia
The problem sounds like it is in the gauge cluster. The entire cluster comes as a single assembly so it is all replaced together.
By any chance do you have a Top Down Technologies' Window Valet installed? I know they had some mode that would send the clusters into a kind of diagnostic/demo state that would hold the needles in a fixed state like that. Probably not your problem but if you have a Window Valet it would be worth pulling it off.
Do the gauges always stop at the exact same locations? Always drop back to zero as soon as the key is turned off? Do the gauges do their full sweep when the key is first turned on?
By any chance do you have a Top Down Technologies' Window Valet installed? I know they had some mode that would send the clusters into a kind of diagnostic/demo state that would hold the needles in a fixed state like that. Probably not your problem but if you have a Window Valet it would be worth pulling it off.
Do the gauges always stop at the exact same locations? Always drop back to zero as soon as the key is turned off? Do the gauges do their full sweep when the key is first turned on?
Thread Starter
Instructor
Joined: Jun 2006
Posts: 241
Likes: 0
From: Gambrills Maryland
The problem sounds like it is in the gauge cluster. The entire cluster comes as a single assembly so it is all replaced together.
By any chance do you have a Top Down Technologies' Window Valet installed? I know they had some mode that would send the clusters into a kind of diagnostic/demo state that would hold the needles in a fixed state like that. Probably not your problem but if you have a Window Valet it would be worth pulling it off.
Do the gauges always stop at the exact same locations? Always drop back to zero as soon as the key is turned off? Do the gauges do their full sweep when the key is first turned on?
By any chance do you have a Top Down Technologies' Window Valet installed? I know they had some mode that would send the clusters into a kind of diagnostic/demo state that would hold the needles in a fixed state like that. Probably not your problem but if you have a Window Valet it would be worth pulling it off.
Do the gauges always stop at the exact same locations? Always drop back to zero as soon as the key is turned off? Do the gauges do their full sweep when the key is first turned on?
No window valet here. When I turn on they do the full sweep then come back and stop on that location. They stop at pretty much the same location. After the car is powered down they go down to 0.
Drifting
Joined: Oct 2004
Posts: 1,384
Likes: 8
From: Southwest Virginia
One other note. It could possibly be a bad connection inside the cluster. If you want to pull the cluster and take it apart I have hundreds of high-res photos of the cluster and things to check. Might be worth a shot. The clusters are fairly easy to pull, and if you need to replace it anyway you have nothing to loose.
Thread Starter
Instructor
Joined: Jun 2006
Posts: 241
Likes: 0
From: Gambrills Maryland
That is a strange problem. Never heard of that before. It sounds like it has to be the logic in the cluster. I have not looked into exactly how the logic drives the gauges, yet. But I'm guessing PWM. But it sounds like for some reason the gauges are not being updated by the cluster after power up. You might try to disconnect the battery for a while. That will force a full reboot of the cluster. The cluster has full time battery power even when the car is off, and part of the cluster will continue to function even if the car is turned off. Unlikely it will fix your problem but worth a try. It sounds like you need a replacement cluster.
One other note. It could possibly be a bad connection inside the cluster. If you want to pull the cluster and take it apart I have hundreds of high-res photos of the cluster and things to check. Might be worth a shot. The clusters are fairly easy to pull, and if you need to replace it anyway you have nothing to loose.
One other note. It could possibly be a bad connection inside the cluster. If you want to pull the cluster and take it apart I have hundreds of high-res photos of the cluster and things to check. Might be worth a shot. The clusters are fairly easy to pull, and if you need to replace it anyway you have nothing to loose.
