Reduced engine power code
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Heel & Toe
Joined: Oct 2013
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Reduced engine power code
I had a dead battery in my C5 after I did a new double din stereo Installation. Once I charged the battery it started right up but then shut down immediately. I did see the msg on the dash that said reduced engine power service immediately. Anybody have any help on what that is and how to fix it?
Moderator, Tech Contributor
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From: Cape Coral, Florida
REP can be caused by a few things…if you don’t have a scan tool use the code retrieving from the DIC and let us know what you see…so now with the radio install you have a start and stall condition…are you seeing any other messages on the DIC ???
Thread Starter
Heel & Toe
Joined: Oct 2013
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OK tried to go into the codes and it wont let me it just keeps coming up with reduced engine power, low fuel cods even after I tried to clear them. Not sure if I am doing something wrong? first time dealing with this. I had a C3 up until about 5 months ago.. haha
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From: Cape Coral, Florida
Sounds like a serial data bus issue…we see this here occasionally…sometimes a bad connection on the drivers door module and the connector is inside that rubber boot when you open the drivers door…shake that boot and see if your problem resolves…the radio install also may also be to blame…if 12 volts or ground backfeeds on the data wire all hell breaks loose.
Thread Starter
Heel & Toe
Joined: Oct 2013
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On the radio install I had Crutchfield do the harness so all I had to do was plug and play so I am assuming (hehehe) they know what they are doing since I bought the stereo from them, and they asked what vehicle I was putting it into. I will check the door boot.
Moderator, Tech Contributor
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From: Cape Coral, Florida
If shaking the boot doesn’t work we will have to access those splice packs near the BCM as in the video…if this all happened after the radio install you should maybe focus on that.
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Thread Starter
Heel & Toe
Joined: Oct 2013
Posts: 23
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yea shaking the boot didnt do anything, but I did notice that the fuel gauge does not register any fuel and it has messages for low fuel, check tire pressure and service engine soon, and I know I have at least 1/4 tank of fuel. Not sure if that adds another layer of if that is all part of the same thing. I will watch the video now. Thanks for your help with this.
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From: Cape Coral, Florida
As in the video remove the “comb” or buss bar off the splice pack that has the 8 wires I believe…you squeeze the sides of the comb and pop it off…now see if your car at least starts and runs…if you have a DVOM you can leave the comb off and with the key on see if you have 12 volts or ground on the radio wire (orange)…a good data line will have a fluctuating voltage of .2 or .3 volts…a scope is needed to see that 0-7 volts !!
Thread Starter
Heel & Toe
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Yea so I watched the video but do not have that test equip. The only wire I tapped into was the e-brake wire (touch screen) right by the handle not of the other wires were messed with. I did put a new cig lighter in as well and used one of the screws by the key to ground it. Would that possibly have anything to do with it? I used the same power wire that was hooked up to the old lighter. The only thing I did was move the ground wire for ease.
Thread Starter
Heel & Toe
Joined: Oct 2013
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As in the video remove the “comb” or buss bar off the splice pack that has the 8 wires I believe…you squeeze the sides of the comb and pop it off…now see if your car at least starts and runs…if you have a DVOM you can leave the comb off and with the key on see if you have 12 volts or ground on the radio wire (orange)…a good data line will have a fluctuating voltage of .2 or .3 volts…a scope is needed to see that 0-7 volts !!
I do have a multimeter so I could check to see if there is 12 volts on the orange wire?
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From: Cape Coral, Florida
Yea so I watched the video but do not have that test equip. The only wire I tapped into was the e-brake wire (touch screen) right by the handle not of the other wires were messed with. I did put a new cig lighter in as well and used one of the screws by the key to ground it. Would that possibly have anything to do with it? I used the same power wire that was hooked up to the old lighter. The only thing I did was move the ground wire for ease.
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From: Cape Coral, Florida
Thread Starter
Heel & Toe
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Moderator, Tech Contributor
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From: Cape Coral, Florida
You can’t have both unplugged for the car to start…the 4 wire splice pack has the BCM and PCM on them…if you have both unplugged or just that splice pack with the 4 wires only you have to jumper the dark green and light green wires for the car to start…PM was sent !!
Thread Starter
Heel & Toe
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OK I did a voltage check on the orange wire and there was none. I did a continuity check between that wire and ground and got. 06 so it didn't zero out for continuity either. When I checked my leads it zeroed out.
Thread Starter
Heel & Toe
Joined: Oct 2013
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yea I didnt have them both unplugged at the same time. one at a time but same results for both.
Drifting
Joined: Mar 2018
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From: New Jersey
If installing the radio is coincident with the no start I would suspect that the radio harness adapter may be affecting the data bus since one of the radio connectors has the data bus on it. If you have the XSVI it connects to the databus so it could be screwing things up. In a later post you say that the orange wire reads .06. That would be a short to ground if you are reading ohms. What is the orange wire?