Hi everyone. This weekend I installed an older aftermarket radio. Nothing fancy just a cd player with an aux input. Ordered a radio wiring adapter off amazon and matched all the speaker wires. Disconnected battery before any work done. Ran one power wire to the under hood fuse box and tied into the fog light fuse ( I never use them ) Upon starting the vehicle radio and all speakers work great, but the vehicle is acting up and throwing all kinds of codes now. I've got a reduced power light, service engine light and here are the codes P1512, P0740, P0785, P1860. Now I am not an expert but I am 99.9% positive that I did not splice into anything I should not have. I have checked fuses and they all seem fine including fuse box under back seat. I have disconnected battery numerous times and cleared codes with scan tool. The vehicle was perfectly fine before all of this. It's just hard to believe that running one wire to the fog light circuity would cause all of this to happen. Any help would be appreciated.
NEED HELP Aftermarket Radio Install 2003 Trailblazer LT
- Thread starter kingcdk
- Start date
I am no expert. Here is my suggestion.
The factory radio has a connection to the onstar system and has an auto volume control based on vehicle speed. My guess is you're getting chatter on the network because those system lost connectivity to the factory radio.
you may need something like this
https://www.crutchfield.com/p_541RP5GM11/PAC-RP5-GM11-Wiring-Interface.html?tp=3486
The factory radio has a connection to the onstar system and has an auto volume control based on vehicle speed. My guess is you're getting chatter on the network because those system lost connectivity to the factory radio.
you may need something like this
https://www.crutchfield.com/p_541RP5GM11/PAC-RP5-GM11-Wiring-Interface.html?tp=3486
Any way of bypassing this? I have reinstalled the factory radio, cleared codes but the problem persists.
xavierny25
Member
@kingcdk a good rule of thumb is all ways clean out your throttle body whenever you disconnect the battery. Otherwise you'll get a few lights flashing at you as well as rough idle and stalling.
This time around remove fuses 10 and 28 in the engine bay clean throttle body, clear your codes and should be good to go.
Edit: I forgot to add wait 30min. Before plugging those fuses back in.
This time around remove fuses 10 and 28 in the engine bay clean throttle body, clear your codes and should be good to go.
Edit: I forgot to add wait 30min. Before plugging those fuses back in.
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Mooseman
Moderator
None of this should affect the tranny and TCC for those codes, except for P1512 which is specific for the throttle position system. This seems to give a good clue as to what to look:
http://www.underhoodservice.com/pulling-codes-what-is-our-position-on-this-the-story-of-p1512/
Just "looking" at fuses is not good enough. You have to test for power on both posts with it in the box. The ETC fuse seems to control this circuit and may possibly control the others. For a bunch of things to happen at the same time like this, it has to be a power or wiring issue. Hopefully you didn't tap into the wrong fuse and bugger up something like the PCM.
http://www.underhoodservice.com/pulling-codes-what-is-our-position-on-this-the-story-of-p1512/
Just "looking" at fuses is not good enough. You have to test for power on both posts with it in the box. The ETC fuse seems to control this circuit and may possibly control the others. For a bunch of things to happen at the same time like this, it has to be a power or wiring issue. Hopefully you didn't tap into the wrong fuse and bugger up something like the PCM.
FearlessAZ
Member
Double/triple check your wiring on the harness and adapter. I was careless one time when installing a deck in my sister's Jeep and connected a wire that I should have left off and car was in a full shut down. Wouldn't let me start or anything. I just assumed since they were both brown wires, that they would go together. I felt so stupid when I had to run it up to a local car audio store and the installer pointed it out.
Not saying that is the cause but something as little as a misplaced wire can cause a lot of shenanigans.
Not saying that is the cause but something as little as a misplaced wire can cause a lot of shenanigans.
Thanks for all the help. I found the problem. So the ground bolts on the fuse panel had been left loose. I think there are 4. I thought I had to take those bolts out to take off a plastic cover, and forgot to tighten them back up. I guess the plastic cover just pops off. Tightened them up and now everything is fine.
