How do I check CAN BUS on my 2005 z71 Tahoe. I understand how to do it through a 16 pin OBD2 port but have no idea how to do it on my Tahoe due to it only having 4 pins in the OBD2 port. Ima supa confused. It has two grounds, data wire, and power wire or voltage wire. Any help on this is much appreciated. Im losing my mind ova here! haha
The reason i need to check this is because I have a major NO THROTTLE RESPONSE issue along with a REDUCED ENGINE POWER message. I have a new throttle body on it. same size as stock. It powers up when i turn the key on and thats it. Codes P0120, P1125, P2120, P2125 are consistent.
Things i have done to fix this issue.
1. checked all wire connections looking for loose ends or damage. I don't see any wire issues but maybe it's super hidden somewhere?
2. Grounds are all clean and tight. I even created a new ground system from the negative terminal to the TAC module, to the Firewall, down to the front side of the head of the engine, to the PCM. Even the "hard to reach grounds on the back of the 5.3" made new ground out of the problem ground ive heard about and cleaned and checked all the wires. Looks good. I have two black grounds that come of the wire harness in the back of the engine. those are good. The only ground i don't have hooked up is the Firewall ground to hood. I doubt that is causing no response from the throttle body. Please correct me if I'm wrong.
3. Tested another TAC and got the same response so im assuming the TAC module is fine.
4. New TPS sensor at the gas pedal was installed. still no response. (it has a pedal adjuster attached to the gas pedal, not sure if that could cause any issues? It currently is not plugged in.)
If anyone can help me understand how to test my new throttle body with a multimeter too that would be awesome. Cant find anything on my year.
Its a fully rebuilt Tahoe. My tuner came over and noticed I had accidentally switched the coil pack plug-ins on the passenger side, he fixed them and the truck started up great. sounded so good! he reved it a couple of times and it sounded awesome, no issues! THEN it happened, turned off the truck, he grabbed the tune kit plugged in and the throttle stopped responding.
Any advice or help on this is greatly appreciated. Its been a week of me trying to fix this issue so I can get my baby rolling again and it hurts my heart so much.
Thank you all for reading and for any future help.
The reason i need to check this is because I have a major NO THROTTLE RESPONSE issue along with a REDUCED ENGINE POWER message. I have a new throttle body on it. same size as stock. It powers up when i turn the key on and thats it. Codes P0120, P1125, P2120, P2125 are consistent.
Things i have done to fix this issue.
1. checked all wire connections looking for loose ends or damage. I don't see any wire issues but maybe it's super hidden somewhere?
2. Grounds are all clean and tight. I even created a new ground system from the negative terminal to the TAC module, to the Firewall, down to the front side of the head of the engine, to the PCM. Even the "hard to reach grounds on the back of the 5.3" made new ground out of the problem ground ive heard about and cleaned and checked all the wires. Looks good. I have two black grounds that come of the wire harness in the back of the engine. those are good. The only ground i don't have hooked up is the Firewall ground to hood. I doubt that is causing no response from the throttle body. Please correct me if I'm wrong.
3. Tested another TAC and got the same response so im assuming the TAC module is fine.
4. New TPS sensor at the gas pedal was installed. still no response. (it has a pedal adjuster attached to the gas pedal, not sure if that could cause any issues? It currently is not plugged in.)
If anyone can help me understand how to test my new throttle body with a multimeter too that would be awesome. Cant find anything on my year.
Its a fully rebuilt Tahoe. My tuner came over and noticed I had accidentally switched the coil pack plug-ins on the passenger side, he fixed them and the truck started up great. sounded so good! he reved it a couple of times and it sounded awesome, no issues! THEN it happened, turned off the truck, he grabbed the tune kit plugged in and the throttle stopped responding.
Any advice or help on this is greatly appreciated. Its been a week of me trying to fix this issue so I can get my baby rolling again and it hurts my heart so much.
Thank you all for reading and for any future help.
it was in bad shape. Wish I would of kept it.
