Corvette505

A couple times when I've started my car after coming back to while sitting in the parking lot for a few hours I would get all these warning messages on my computer. For ex. Reduced engine power, service vehicle soon, and others. This happened a couple times about a month or so apart. Now it's showing up when I start it! My car has just reached the 120,000mi mark aswell. What is the best approach to solving this problem? Any help is greatly appriciated.k

glbeauchamp

I guess the first things I would check would be the grounds, then test for a weakening battery.

Phanni

Do you know how to read the codes? If so, that is the starting place.

Jeff T.

Just in case, here's how to read the codes.

Corvette505

I am also experiencing passenger door power loss. Could this be of the same result in the battery? The window lock and mirrors don' work unless I fully open up the door.

Vetteman Jack

Moved over to C5 Tech.

BigGun

The door problems along with the messages suggest a problem with serial bus connections. You need to codes to see if that could be the issue.

RedRiderZR1

I am having the same exact issue as of last night. But my problem is in the drivers door. Mine is a serial buss issue since when I pull codes, every module reports NO COMM. Looks like the serial buss wire is shorting to ground. Sounds like you are having the same issue, but in the passenger door.

Pull codes and see what errors you are seeing. Do you have a Christmas light display in your IPC?

GCG

You didn't say which codes you're getting, but what's happening with your passenger door sounds like bad contacts in the connector inside the door's rubber accordion. Therefore, I wouldn't be surprised if there are codes present as a result of loss of communications through the Serial Data Bus.

This problem has been extensively documented by Bill Curlee and you can read more here, but you should start by listing all codes you're getting.

The Serial Data Bus goes through the rubber accordion to the door control module. The female pins of the connector on that wire harness get deformed, causing bad contacts and loss of communication/corruption in the Serial Data Bus affecting all modules linked by it.



You can troubleshoot by opening the Star Connector 2 by the passenger's foot well, which isolates both Door Control Modules along with the Left Seat Control Module, and if communications are restored then you have your culprit.

Check the connectors for deformed pins. If bad pins are found you would need to repair the connector, fixing the female pins so they have a positive grip, or replace it. If you want to replace the connector take a look at this post for some ideas.

jim993

If the symptoms change significantly or disappear when you turn the ignition key off and re start the engine, the ignition switch is a possible culprit.

If the ignition switch is failing, burned internal contacts will cause a wide variety of symptoms, often different each time you attempt to start the engine and sometimes going away completely for that start and run cycle.

Before replacing the second defective ignition switch on my 2001, the DIC displayed symptoms such as REDUCED ENGINE POWER; LOW VOLTAGE, SERVICE ACTIVE HANDLING various lost com and others. The last time that happened, the engine would hardly go above idle. Then a re start extinguished all the warnings and the car drove normally but displayed a CHECK ENGINE light. A new ignition switch cured the problems.