Speedometer problems

Huntintruck · October 1, 2005

The speedo on my wife's Yukon seems to get stuck in varying locations. I can start the car with the speedo regestering 10mph, and it will correctly meter if you subtract the 10mph. such as 40 actually means 30mph. The location changes every time I turn the car off, and can sometimes stop at the high limit. The other gauges operate correctly. Is this something in the speedo that is loose, or can be repaired, or must the cluster be replaced. Is this a do it yourself job? I was told by a GM service manager that the odometer was kept in the main computer, but I read another post here that stated that the mileage is kept within the instrument cluster, and replacement is a jop for Mr. Goodwrench, if the actual mileage is to be transfered to a new speedometer.

Thanks,

pastor scott.com · October 3, 2005

On my 04 burb, the speedo went out at 20,000. it started climbing one night all the way to 100MPH then back and then it really got crazy. Dealer replaced it NO CHARGE or QUESTIONS.

Scott

GM-Tech · October 1, 2005

If at any time, the needle stays anywhere above zero when the key is off, the cluster needs repair. I wouldn't say I've seen that a lot, but we've repaired a few.

The "where is the mileage stored" question is an oft debated topic. I'm here to tell ya that it is only in the cluster itself on the trucks (some car models have it in the BCM). It has also been debated that it must be hidden elsewhere in some other module so we can access it and tell if you're trying to pull a fast one with an altered odometer. If it is elsewhere, it is hidden so well that it is not accessible by any means available to a GM dealership.

We do the cluster repair one of two ways. We call the authorized AC Delco repair facility and they send us an exchange cluster with the correct mileage programmed in to it. We send the defective cluster back when we get the exchange unit, and the one we send back had better have the mileage that we told them to program into the exchange unit. They've told me personally that if the mileage isn't correct, they have to call the police and report it.

Or... We send out the defective cluster and it is repaired. That's if no exchange is available. Obviously, mileage is not an issue in this case because that won't change.