Hi guys and gals,
2009 Avalanche LTZ (Eco)
I searched for this combination and found a couple of threads that were similar, but not quite enough. I am sure I missed one that is the same, it seems to happen every time. Here is the history:
2017 February - Gm certified rebuilt transmission installed
2019 March - P0121 replaced throttle positioning sensor.
2019 September - Transmission rebuild and transmission control module replaced
2019 October - P0700 and U0073 Hard downshifts, flare at 3k rpm up shifting, Stabilitrack service warning.
-Dealer throws up there hands and shrugs their shoulders. Resets codes
-Truck drives basically normal
2019 November - P0121 is added to the mix
-Dealer blames the throttle positioning sensor, that was replaced a few months ago.
-Resets codes again. Trucks drives basically normal again.
I am not interested in throwing more parts at it with the dealer at this point. What is going on here? I know I am not the first person to see this issue. What set off the P0700 (generic Transmission code to trip MIL) and U0073 (Control Module Communication Bus 'A' Off)? Where should I start looking at to find the problem? I don't care if the dealer fixes it (because they warranty the work), but I want a good idea of what is going on because when I am correct, my dealer doesn't charge me for the diagnostic if I am correct. We have used the same dealer for a couple generations now.
So, ideas on the P0700 with U0073? Why did it later trip the p0121? I just had the TPS replaced.
TIA
Myke
2009 Avalanche LTZ (Eco)
I searched for this combination and found a couple of threads that were similar, but not quite enough. I am sure I missed one that is the same, it seems to happen every time. Here is the history:
2017 February - Gm certified rebuilt transmission installed
2019 March - P0121 replaced throttle positioning sensor.
2019 September - Transmission rebuild and transmission control module replaced
2019 October - P0700 and U0073 Hard downshifts, flare at 3k rpm up shifting, Stabilitrack service warning.
-Dealer throws up there hands and shrugs their shoulders. Resets codes
-Truck drives basically normal
2019 November - P0121 is added to the mix
-Dealer blames the throttle positioning sensor, that was replaced a few months ago.
-Resets codes again. Trucks drives basically normal again.
I am not interested in throwing more parts at it with the dealer at this point. What is going on here? I know I am not the first person to see this issue. What set off the P0700 (generic Transmission code to trip MIL) and U0073 (Control Module Communication Bus 'A' Off)? Where should I start looking at to find the problem? I don't care if the dealer fixes it (because they warranty the work), but I want a good idea of what is going on because when I am correct, my dealer doesn't charge me for the diagnostic if I am correct. We have used the same dealer for a couple generations now.
So, ideas on the P0700 with U0073? Why did it later trip the p0121? I just had the TPS replaced.
TIA
Myke
