[Z06] Dreaded "reduced engine power"
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,281
Likes: 21
From: Orlando Florida
Dreaded "reduced engine power"
came on briefly on Saturday.
I was sitting on post at the shop waiting for a bay to open up. Backed into a spot and opened the windows. Saw the "reduced engine power" and thought that was strange, never seen it before. Then the driver side door controls wouldn't work, none of them would.
Tried the passenger side controls and those worked.
Tried starting the car and it started fine. Decided to head home at that point, driver side controls still would not work and the doors did not auto lock like they usually do at 10mph.
Also noticed that oil and water temperatures were high. Oil was 220 and water was 230. Figured that thermal inertia had them rising after I stopped the car and there was no fan or air forced underneath to cool it.
After driving for about 5 minutes, the temps dropped back to normal.
From my reading, it seems that the main culprits could be:
weak battery
alternator
G101 ground
G102 ground
Those are all pretty simple to check.
Any other suggestions?
I've also read that low coolant could possibly cause this. Is this true?
I was sitting on post at the shop waiting for a bay to open up. Backed into a spot and opened the windows. Saw the "reduced engine power" and thought that was strange, never seen it before. Then the driver side door controls wouldn't work, none of them would.
Tried the passenger side controls and those worked.
Tried starting the car and it started fine. Decided to head home at that point, driver side controls still would not work and the doors did not auto lock like they usually do at 10mph.
Also noticed that oil and water temperatures were high. Oil was 220 and water was 230. Figured that thermal inertia had them rising after I stopped the car and there was no fan or air forced underneath to cool it.
After driving for about 5 minutes, the temps dropped back to normal.
From my reading, it seems that the main culprits could be:
weak battery
alternator
G101 ground
G102 ground
Those are all pretty simple to check.
Any other suggestions?
I've also read that low coolant could possibly cause this. Is this true?
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,281
Likes: 21
From: Orlando Florida
I could see that happening, computers can get weird. But I do not have a tune and have never messed with the PCM in any way. I will end up getting a mail order tune after I get my headers installed (hopefully this weekend).
7th Gear
Joined: Feb 2010
Posts: 7
Likes: 0
From: New Orleans Louisiana
I was having the exact same problem with mine. The car was briefly losing communication with the LDCM (Left door control module) and was freaking out! Turns out the wire clip in the door was loose for some reason. Stuck my hand in, clipped it back, haven't had an issue since. A friend of mine had same problem but with the RDCM. Check out the codes, see if you are throwing any for either the LDCM OR RDCM.
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,281
Likes: 21
From: Orlando Florida
These are the codes I'm getting:
10-PCM P1626 H
28-TCS U1301 H
40-BCM B2592 H
40-BCM U1255 H
40-BCM U1016 H
40-BCM U1096 H
58-SDM U1301 H
60-IPC U1255 H
60-IPC U1016 H
60-IPC U1064 H
60-IPC U1040 H
60-IPC U1088 H
60-IPC U1176 H
80-RADIO U1064 H
80-RADIO U1016 H
80-RADIO U1096 H
99-HVAC U1064 H
99-HVAC U1096 H
99-HVAC U1160 H
99-HVAC U1255 H
AO-LDCM U1064 H
A1-RDCM U1255 H
A1-RDCM U1064 H
A1-RDCM U1016 H
A1-RDCM U1096 H
A6-SCM U1300 H
A6-SCM U1255 H
BO-RFA U1255 H
BO-RFA U1096 H
BO-RFA U1016 H
10-PCM P1626 H
28-TCS U1301 H
40-BCM B2592 H
40-BCM U1255 H
40-BCM U1016 H
40-BCM U1096 H
58-SDM U1301 H
60-IPC U1255 H
60-IPC U1016 H
60-IPC U1064 H
60-IPC U1040 H
60-IPC U1088 H
60-IPC U1176 H
80-RADIO U1064 H
80-RADIO U1016 H
80-RADIO U1096 H
99-HVAC U1064 H
99-HVAC U1096 H
99-HVAC U1160 H
99-HVAC U1255 H
AO-LDCM U1064 H
A1-RDCM U1255 H
A1-RDCM U1064 H
A1-RDCM U1016 H
A1-RDCM U1096 H
A6-SCM U1300 H
A6-SCM U1255 H
BO-RFA U1255 H
BO-RFA U1096 H
BO-RFA U1016 H
Melting Slicks
Joined: Oct 2008
Posts: 2,946
Likes: 55
From: b.b. n.j.
These are the codes I'm getting:
10-PCM P1626 H
28-TCS U1301 H
40-BCM B2592 H
40-BCM U1255 H
40-BCM U1016 H
40-BCM U1096 H
58-SDM U1301 H
60-IPC U1255 H
60-IPC U1016 H
60-IPC U1064 H
60-IPC U1040 H
60-IPC U1088 H
60-IPC U1176 H
80-RADIO U1064 H
80-RADIO U1016 H
80-RADIO U1096 H
99-HVAC U1064 H
99-HVAC U1096 H
99-HVAC U1160 H
99-HVAC U1255 H
AO-LDCM U1064 H
A1-RDCM U1255 H
A1-RDCM U1064 H
A1-RDCM U1016 H
A1-RDCM U1096 H
A6-SCM U1300 H
A6-SCM U1255 H
BO-RFA U1255 H
BO-RFA U1096 H
BO-RFA U1016 H
10-PCM P1626 H
28-TCS U1301 H
40-BCM B2592 H
40-BCM U1255 H
40-BCM U1016 H
40-BCM U1096 H
58-SDM U1301 H
60-IPC U1255 H
60-IPC U1016 H
60-IPC U1064 H
60-IPC U1040 H
60-IPC U1088 H
60-IPC U1176 H
80-RADIO U1064 H
80-RADIO U1016 H
80-RADIO U1096 H
99-HVAC U1064 H
99-HVAC U1096 H
99-HVAC U1160 H
99-HVAC U1255 H
AO-LDCM U1064 H
A1-RDCM U1255 H
A1-RDCM U1064 H
A1-RDCM U1016 H
A1-RDCM U1096 H
A6-SCM U1300 H
A6-SCM U1255 H
BO-RFA U1255 H
BO-RFA U1096 H
BO-RFA U1016 H
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Melting Slicks
Joined: Jan 2007
Posts: 2,246
Likes: 0
From: Ball Ground Georgia
St. Jude Donor '11
Clear those codes. Anything with an "H" after the number is a history code, and not something currently taking place. After clearing, keep check on it and see if anything comes back up. If so, then you have your culprit.
Pro
Joined: Oct 2007
Posts: 738
Likes: 52
From: Reno NV
It means you have Data Bus Line communication problem with wire that runs through the car. If that wire or a sensor gos out, Pinched wire, dirty ground etc... You will experience what you are describing.
Your battery and alternator can cause maybe similar problems if they go out too.
Your battery and alternator can cause maybe similar problems if they go out too.
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,281
Likes: 21
From: Orlando Florida
Cleared the codes and took the battery out to get it tested. It would not hold a charge so I got a battery. Just picked up an Interstate at Sam's. I've heard good things about them.
Instructor
Joined: May 2009
Posts: 156
Likes: 0
From: honesdale pa
I had same issue with driver's side controls, pulled the door to body accordian out of body and found bare wire sticking out of connector, put a little liquid electrical tape on it and all is good! 
