MonolithMonolith

So I got the Reduced "Engine Power/Service Traction Control/Service Active Handling" message last night, and twice today. Last night for the first time ever it came on about 10 to 15 seconds after I hit a big pot hole. I noticed the windows were fogging up, tried rolling the window down, no power, immediately pulled over and as I did, the check engine light came on along with the warnings. I let it sit for a bit (10 mins) and started it up and everything was fine.

Today I backed it out of the driveway, let it idle for a few, pulled it back in, and it did the same thing. I shut it down, let it sit for a few, came back out to run codes, and it was fine.

Later on, driving around for about an hour, was in a parking lot and it came on. I pulled over, ran the codes, then drove it home. It was chiming the whole time but power was NOT reduced, at least not like people were saying in some threads. It seemed to drive normal with the messages. Also would not let me toggle traction control.

These are the codes I pulled:
10 Powertrain Control Module
P0133C/Heated Oxygen Sensor (HO2S) Slow Response Bank 1 Sensor 1
P1626H/Theft Deterrent System Fuel Enable Circuit
(I have a cam and tune and they were supposed to tune out the rear O2s. Is the 1033c related?)

28 Traction Control System
U1301H/Class 2 Circuit Shorted to Battery
C1221H/LF Wheel Speed Sensor Input Signal is 0
C1222H/RF Wheel Speed Sensor Input Signal is 0
C1248H/Dynamic Rear Proportioning Disabled

40 Body Control Module
U1255H/Serial Data Line Malfunction
U1096H/Loss of Communications with Power Control Module
U1016H/Loss of Communications with Instrument Panel Cluster

58 Steering and Diagnostic Module
U1301H/High voltage on the class 2 serial data circuit.

60 Instrument Panel Cluster
U1255H/Lost Communication with XXX
U1016H/Loss of Communications with Power Control Module
U1064H/Loss of Communications with Body Control Module
U1040H/Loss of Communications with Traction Control System
U1176H/Loss of Communications with Remote Function Actuation
U1088H/Loss of Communications with Sensing Diagnostic Module. Refer to DTC U1001‐U1254 Lost Communication with XXX Instrument Panel Cluster
U1160H/Loss of Communications with Left Door Control Module

99 HVAC
U1064H/Loss of Communications with Body Control Module
U1096H/Loss of Communications with Instrument Panel Cluster
U1160HC/????
U1255H/Serial Data Line Malfunction

A0 Left Door Control Module NO COMM

A1 Right Door Control Module
B2283H/Battery #1 Fault
B2285H/Battery #2 Fault
B2265H/Horizontal Position Sensor Fault
U1255H/Serial Data Line Malfunction
U1064H/Loss of Communications with BCM
U1016H/Normal software function, history status upon ignition cycling
U1096H/Loss of Communications with IPC

A6 Seat Control Module NO COMM

BO Remote Function Actuation
U1255H/Serial Data Line Malfunction
U1064H/Loss of Communication with BCM
U1096H/Loss of Communication with IPC
U1016H/Loss of Communication with PCM


Mods are: LG headers, Cam, Tune (supposed to remove rear o2's), catback exhaust/no cats, K&N Cold air intake, ported throttle body, corbeau seats (explains no communication with seat control module), aftermarket wheels/tires/brake rotors/pads. I also have a stereo system I installed. Sub is grounded to the body behind the drivers seat.

That's all the info I think is important right now. Any help or ideas? Should I clear them all and see what comes back? Most are "history", so it's hard telling how old they are.

jim993

With all those codes, I think the fine after restart would point me to the ignition switch. The contacts get burned and sometimes make contact, sometimes not. When they don't make good contact, you can get multiple warnings on the DIC, which often disappear with a restart.

Your symptoms are similar to what I had with each of two ignition switches, 2-1/2 years apart.

If it is the ignition switch, it is hard to diagnose. The clue is an immediate OK restart or a restart with fewer DIC warnings with no other changes.

If it gets bad enough, you can diagnose by checking voltage at underhood fuse 16, which powers the PCM.

Bill Curlee has a number of posts which describe similar problems resulting from bad connections developing in the wiring to the door(s), I think driver door first. He may also respond or you may be able to search his posts. The door wiring connectors are accessed via the rubber bellows at the door post area. If opening the door or wiggling the wiring at the bellows area has an effect on codes or operation, look there.

MonolithMonolith

So does it disable drivers side door power for safety reasons during the Reduced engine power mode? If I remember correctly, I could still roll my passenger side up with that side, and the door lock would work on that side, but not the drivers. It was as if it cut power to it fully. I'm still researching and digging in the threads, but I am swamped with work for the next week and am hoping to get some answers here.

(Thanks for any input from anyone!)

jim993

It does seem unlikely that you would lose just one door if the ignition switch is the culprit. I might look into the driver door rubber bellows and connector first. It is certainly easier to get to.

martysauto

That's a lot of u/com codes. The p0133c is a primary o2 code, more than likely the sensor is getting lazy. I have seen modules fail and take out the whole communication network. Ebcm's are problematic.
I would suggest clearing everything. Run it and see what comes back. Before you get to far into it, you should double check all your new stereo wiring. Did you just install the radio?
If the stereo install is ok and all the com codes come back, you can unplug the ebcm. Then run it and see what comes back. if you drive it, take it easy. You will get warnings and codes.
You are looking to see if the comm codes do not come back for all the other modules. If not the ebcm is probably shorting out the network
I do agree with jim933, gm ignition switches can cause bizarre problems. If you change it go o.e., not aftermarket!
Hope this helps!

MonolithMonolith

Stereo install has been within the last couple months. October time frame it went in. Sub/Amp went in a month or two after. I did it all myself, and I'm pretty good about it. I soldered the wiring, then put heat shrink tubing on it, zip tied it out of the way, etc. I am going to pull the radio to look into wiring on it because every now and again, it won't come on unless I tap it or let it sit for 15 seconds or so. Also, I'm going to check the amp wiring along with the ground when I get out of this leadership school I'm in.

echelonphoto

It is a wire in the door accordion....there is a wire where the insulation does not quite cover the bare wire...do a search on door accordion

3boystoys

I agree with the accordion but it's not the wire(s), it's the PINS in the connectors. If you open the drivers door when this happens and GENTLY pull on the black tube connecting the door and the chassis and things begin to function, you found your issue. Plenty of posts on this problem, the female connections become deformed over time and you start to get flaky connection making the data bus go CRAZY.

MonolithMonolith

You know.....I DID have a can of sprite explode in my car right next to the passenger seat the same day all this crap happened......it didn't completely drain though....I'm gonna look into the door wires and the passenger side to check for dampness when I get a chance.

dadaroo

With regard to the radio issue. Check the wiring in the passenger side where it goes around the metal support bracket. You could have a chaffing issue there like a friend of mine, the metal is sharp and the wiring not well protected. Could have a similar issue on the driver side. Just giving you more crap to think about.

I completely agree the ignition switch is a real weak point. Mine works fine but at 60K miles I plan to replace it since I have the knee bolster off right now.