Mileage doesn't work but odometer and trip work. Digital dash

I have a 2007 Saturn Aura XR. 3.6 My issue is the odometer works and the trip also but the mileage doesn’t change. I replaced the transmission and since then the mileage doesn’t work. I’ve switched the cluster with a different
one and same thing. This tranny has only one plug in for everything. I’ve checked the prongs and everything looks fine. The strange thing is that trip works and odometer…Any ideas?

What exactly doesn’t work? Do you mean the speedometer doesn’t work, but both odometers do work? Or is it the mpg display that doesn’t work, but the speedo and odometers do work?

The mileage… everything else works fine The odometer works, the trip works fine, just the cars mileage never changes.

The odometer is the cars mileage…
your post is mildly confusing as to what your actual issue is. Can you clarify for us?

The Speed odometer works fine so I know how fast I’m going, the trip works fine so I can see how far I’ve traveled on a trip. It just the mileage so I can tell how many miles are actually on the car that doesn’t work.

I think you’re saying the digital odometer displays a mileage reading, but that reading never changes? But the trip mileage does change? I know GM had some instrument cluster issues, but that is an odd one. You’d think the computer would use the same input to calculate the trip and odometer mileage. Or maybe I’m way off base and my understanding of the problem is incorrect?


Similar problem-

Anyone messing with the cluster or BCM?

Your nomenclature is confusing us. There’s no such display in a car called a “speed odometer”. There’s a “speedometer” to display vehicle velocity in miles per hour, and an “odometer” to display distance traveled in miles, one for the entire life of the car (odometer), and one the most recent trip (trip odometer). “mileage” or “gas mileage” usually refers to the vehicle’s fuel efficiency, measured in miles per gallon. Many newer cars have that dash display in addition to the ones above. Suggest you use this terminology to avoid confusion here.

It appears your problem is that the life of the car odometer display isn’t correct and isn’t changing as you drive. Since the other displays are correct, that’s likely a problem with the console-display (instrument cluster) unit. It probably has to be removed and either repaired or replaced. Google “gm instrument cluster repair”, you’ll probably get a list of some companies that do this sort of work. If you phone a few of them up and tell them your symptom, they’ll probably have heard of it before and know what you should do next.

I think you’re right on target @Scrapyard_John. Assuming that the odometer mileage is tracked by the ECU or some other module, and the trip meter is working as it should, I would have to think that something is wrong with the odometer section of the ECU or module.

Ok thank you. I’m going to send it to be repaired.