2002 Chevy Trailblazer electrical problem with passenger door

electrical-wiring
chevrolet
trailblazer

#1

Recently all electrical in the passenger door stopped working: power locks, power window, power mirror. Even the dome light doesn’t come on when the passenger door is opened. One mechanic said it was Driver door master lock module, another said it was short with ground. Any thoughts?


#2

My guess is there may be a plug for the electricals in the door located in the door jam and the plug is loose. Try reseating the plug if there is one.


#3

I would start with an exam of the schematic to see just how everything is related and what is possible.


#4

There is a plug at both the Driver’s door and car body and passenger door and car body, both were seperated, cleaned and repluged. This didn’t solve the problem. We also checked the relays and fuses for the passenger door and that didn’t work either. Actually one Chevy dealer said it was the Driver’s door master door lock control module, a part that sells for $750, while another Chevy Dealer said that 2002 was too early for a master door lock module and it was a $250 switch in the passenger door, both want at least two hours (at $90 and hour) diagnostic time to pinpoint the problem.


#5

Noone seems to have a schematic for the 2002 model year. A local mechanic is leaning towardsa broken ground, based on the dome light not going on when the door is opened. The button, on the driver’s door, that stops all windows from opening is no longer working.


#6

I assume that all the things you mentioned went out at the same time and if so that would point to a common point of failure in my book. While the dealer knows more about the car than I do, I don’t think that the master lock module has any control on the switch for the dome light and possibly the door locks. I could see it controlling the window and mirror though. To see if this is a ground problem you could try running a test jumper between the chassis and a good ground point on the door though I have my doubts that will help in this case. I suspect a power problem is the cause but I have been wrong before and may be again.

The 250 dollar switch that one dealer talked about could be the problem if it ties to all the things you mentioned. I would guess the switch contacts could be cleaned if that is the case. You should be able to get some data from alldata.com I would think and the info would be well worth the purchase cost to help find the source of the trouble. If you are going to keep the car for some time I highly recommend you purchase a factory service manual for it along with a test light probe and a DVM meter, if you want to work on things like this yourself. These things will save you a lot of money in repair costs and time an can pay for themselves in just the first repair.


#7

Thanks for your input. Actually the problem was intermittant, then the door went completely dead and has remained that way.


#8

You really need to look harder for a schematic. Schematics are the key to fixing a complex problem such as this.


#9

I assume that the intermittent failure effected all the things you mentioned which still points to a common failure point and something like a loose connection or bad switch connection. I still don’t see how there could be a single switch involved, inside the door, that would tie to all these things.


#10

To all that made suggestions, thank you. We have solved the problem, it was a faulty swith on the passenger door console. The panel that has the electric window opener and power lock switch snaps out of the door, there is a module below it that takes three plug in connectors. One of them was bad. A quick trip to the local recycle yard for the switch module and $25 later all is well.


#11

Glad to hear that you solved the trouble. The tech that told you about the module in the door was correct and you saved a lot of money doing this yourself. Thanks for the feedback.

If you are go to keep this vehicle you should consider purchasing a factory service manual with some of the money you saved on the repair.