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2004 Tahoe "reduced Engine Power"

Fetchgun

By Fetchgun
in Ask A GM Technician

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Fetchgun Enthusiast

Fetchgun

Posted
Posted

Codes p2135 p1516 p0220

I have 2004 Tahoe that goe into reduced engine power and stability control diabled while driving. I have read around the net, and this is what I have done so far: Replaced APP, Ohmed out the wiring between the TAC and the APP then the TAC and the TPS. All wires were below .5 ohms. I also tugged on the wires 6" behind TPS connector while taking the resistance readings with no change. Replaced the TPS/TB combo. Counld not get to the ground connections on the bolck. I think they were G102 and G103?? I there any way to test the grounds? Does the TPS have its own ground connection? Is there anything else I should look for??

 

 

 

Thank You

Bobby

ChevyTech77 Senior Enthusiast

ChevyTech77

Posted
Posted

Grounds are best checked with a loaded voltage drop test.

 

Replace all the TAC circuits, with new terminals, from the TAC module to the TB. Seen

quite a few of these with the same issue.

Fetchgun Enthusiast

Fetchgun

Posted
  • Author
Posted

Are

Grounds are best checked with a loaded voltage drop test.

 

Replace all the TAC circuits, with new terminals, from the TAC module to the TB. Seen

quite a few of these with the same issue.

 

Are the circuits dedicated from the TAC to the TB ? Where can run all new wiring . You wouldn't happen to have a part number for the TAC connector would you? I did find the TB pigtail.

 

Thanks again

Bobby

Fetchgun Enthusiast

Fetchgun

Posted
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Posted
I've had the same thing happen to my wifes 03 Yukon twice in the last 6 months or so. What exactly is the APP and the TAC?

 

APP= Accelerator Pedal Position Sensor is located on the accelerator pedal that talks to the TAC

TAC= Throttle Actuator Control Module talks to the APP and the TPS to make sure they are on the same page.

The TAC I'm hoping is the box on the fire wall on the drivers side.

  • 7 months later...
MelAmos New Member

MelAmos

Posted
Posted
I've had the same thing happen to my wifes 03 Yukon twice in the last 6 months or so. What exactly is the APP and the TAC?

 

APP= Accelerator Pedal Position Sensor is located on the accelerator pedal that talks to the TAC

TAC= Throttle Actuator Control Module talks to the APP and the TPS to make sure they are on the same page.

The TAC I'm hoping is the box on the fire wall on the drivers side.

 

 

 

I have been reading forums now about the reduced engine power signal coming on, i have recently had a fuel pump put in my 04 Tahoe, got it back and now my ses light came on and rep signal! It seems theres alot of problems related to this, I dont want to put lots of money into my truck and not have the problem solved! So what im wanting to know if anyone has seemed to get their problem fixed???? Thanks so much

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