Tahoe Speedometer Issue - Anyone know?

fxdm70

Hi Guys, I just bought a 2005 Tahoe LT / 2wd. Had a pre inspection done and car came back rock solid.

Driving it home last night (300 miles) I had the cruise control on about 70 MPH -- When I slowed down for whatever reason, the speedomerter slowly dropped to zero and would no longer work.

The cruise control WOULD work. So I put the car in neutral, shut it off and restarted it. The speedomerter started working but the cruise WOULD not work.

I stopped the vehicle and parked it for 20 minutes. After I restarted it -- everything worked fine.

Can anyone tell me what could possibly cause this??

Thanks!!!

kiawah

There's three pieces to this, the sensor on the transmission which detects each revolution, the engine computer, and the speedo display.

In your first scenario, you indicate the cruise was continuing to work, which would indicate that the sensor and computer were still working, but the display was out. Display being out could be either the computer feed to the display, or the display itself. Normally you would think the display was bad.

In the second scenario you indicate that the speedometer was working, but not the cruise. In order for the speedometer to work, you would have to have the sensor working as well. So the sensor, a piece of the computer, and the display was working, but the computer cruise logic wasn't.

Unfortunately, I'm suspecting your engine computer is bad. I would continue driving it however, to validate and confirm the failing scenarios.

fxdm70

Great... any idea how much a engine computer is ????

rodonnell

Probably not the computer. My speedometer does the same thing, especially when it is very cold outside. Cruise control works fine. And the odometer works fine as well. I just received a notice from GM mentioning a faulty gauge cluster that caused erratic readings. They thoughtfully mentioned they were extending the warranty for this piece to 70K miles. Unfortunately I have 90K. I suspect there is an electrical problem in the cluster, or maybe the shaft of the speedo needs a little lubrication.

fxdm70

Thanks so much. I hope this is the problem...

jjoner123

I would greatly appreciate it if you would send a copy of the letter that GM sent. The dealer is telling me that in order to fix the issue under the coverage he needs the letter and when I called GM customer service they said they couldnt send a copy of the notice to me. Im furious.

Thanks, J. Joner

Jjoner@yahoo.com

andy151

I have an 04 Tahoe Z71 that the speedo works sometimes and sometimes it gets stucks sometimes just doesnt work at all. If you could send me a copy of that letter I would appreciate it. I have to tell my dealership what is going on with it and they said that they would help me since I just bought it. If it could be anything else please let me know.

andy.green82@yahoo.com

thanks so much

pb5

I have a 2005 tahoe with 76000 mi speedometer went out contacted one dealer said he would fix it for 188.00. I prayed, contacted the dealer where i purchased the vehicle and they said they would fix the car for free! T :shades: THANK YOU JESUS!