[TERRY WILL]

I am getting the other Suburban. Previous owner saw large wet spots under the back side of the engine and on the ground and was told that the rear main seal was shot and to just keep plenty of oil in it... It is 2 quarts over right now, and no significant oil leakage. I crawled under it while it was running and gas is spraying from a tiny hole that was rubbed through the stainless high pressure line from the tank by a small bracket that was not secured to the body. Think I found the "oil leak". Gonna patch it and drive it home this weekend.

 

[Motor City Rick]

Center dash area is where your gonna find it.

If your gonna clean the drivers door lock switch, only two things can be used:

One is "electronic tuner cleaner" (NO OTHER CHEMICALS!!!).
Two, high pressure compressed directed air that can be directed into any seam, rocker lever area or open point in the switch body.

This procedure "might" work, but if your at that point, get a good high quality switch from Rock Auto.
Remember, ...you have a 21 year old vehicle. Save on the grief, ...replace the 21 year old switch.

 

[thegawd]

I have had limited success fixing these switches. First thing is to try not to break the fragile plastic while dissembling it. Its a simple machine, the buttons are mechanical and they rock on a circuit board. The circuit board will be where the problem lies. I have cleaned these boards with rubbing alcohol or acetone and a qtip. Remove the dirt and the corrosion and hope you can put it back together.

This works very well for the mirror switch as well... when mirrors dont work this usually fixes them.

I always try to fix things like this before replacing them. when i fail i go to my local u pick junk yard and for a fraction of the price of new i will buy as many decent looking switchs as i can find, test them all, fix or throw out the broken ones and stock pile the rest. So far on the 2 trucks i have , i have only bought a new 4x4 selector switch.

Al

 

[thegawd]

There are quite a few of these switchs available on amazon, aftermarket and oem. Price from $15-75. Standar motor products has great reviews, much better than ac delco... they say beware of the ac delco its not official.... reviews are everything.

Al

https://www.amazon.com/s?k=1995-1999 Suburban Power Window Master Control Switch&ref=is_s

 

[TERRY WILL]

I found an excellent You Tube video of the switch disassembly and cleaning showing exactly where to pry etc. to avoid breaking tabs. The way it's acting there must be something on the circuit board itself that is allowing stray current movement.

 

[thegawd]

Can you post the video Terry? I had a quick look but couldnt find one.

 

[TERRY WILL]

GMC / Chevy Truck - Power Window & Power Lock - The Fix

I am so old school I have no idea how to post the video here, but here is the title!

 

[thegawd]

Excellent Terry thanks! With YouTube you can just copy the video web address and paste it here on gmtruckclub. But the title also works to get us there.

Al

 

[Glen Spino]

Judging by all the good clues, I suspect it's not the relay itself, but a short that causing the relay to engage/disengage. I once had wiring damage from a mouse that invaded my dashboard. Surprised the neck outta me when he poked his head out the dash vent. Since then the onboard computer would wig out at the most inconvenient times, particularly when going downhill.

 

[TERRY WILL]

I once had a mouse take up residence in my 64 GMC. Every time I started up the truck for weeks and let the heater core get warm he would run out the defrost vent, scurry across the dash and chatter at me as if I was ruining his whole world. Then one day he tried that stunt and I had the wing window open, he lost his footing and out he flew. I could see him in my mirror sitting on the edge of the road looking stunned for a second, so I hit the brakes to stop and watch. He quickly darted into the ditch. Last mouse I have had in any of my rigs. Put heavy screen over the fresh air inlet on all my rigs from then on.

 

[TERRY WILL]

So... working in the yard and CLICK CLICK! And the the main switch is not plugged in. Could the lock sensor for the auto lock when moving be bad, and if so is it located on the transmission or where?

 

[Motor City Rick]

I'm leaving some addition schematics with a different layout.

Next will be pulling one lock relay at a time to see if it's an "up" issue, or a "down" issue which will be in the power distribution center in the engine bay.

If my power distribution layout is wrong, then take a good quality picture of what you have.

 

[TERRY WILL]

So I got the key fob lock/unlock working and after cycling the locks a few dozen times, and lubing all the lock linkages, and cleaning the terminals at the top of the right rear door, the rear door actuator stripped out. I removed it, and for about 3 hours all was quite on the western front so I went to start on another project, and...CLICK CLICK, so I hurried and got in the Burb and felt the remote control door lock receiver, the doors cycled lock-unlock by themselves and it was not actuating. I hit the key fob while holding on to the remote control door lock receiver and felt a distinct click. I will have to pull the plastic from around the side that has the power door lock relay and pray that they do their magic while I am feeling it. I may try pulling #13 fuse and disabling all the door switches then take it for a drive and see if it locks when I hit MPH. It may be that it needs the rear actuator in working condition.

 

[TERRY WILL]

So the rig I bought with water in the oil turns out it has a bad intake gasket, not a blown head gasket or cracked head, I bought a fourth suburban that has a new transmission and unknown engine problems. Now how to decide which ones to fix and which one to use for parts. The one that was supposed to have a bad rear main seal had a hole rubbed in the steel low pressure fuel return line b y the firewall, a 1" slit piece of rubber line slipped over it and a hose clamp and she ran perfect all the way home while towing my GEO, then the service 4 wheel drive light on the dash lit up and the lights on the 4X4 switch went dark. Now there is a lot of clicking coming from a metal box under the dash to the left of the steering column. It has two 10 MM headed bolts holding it in place and seems to have one large multi pin plug on the side. I am hoping it is just the switch flaking out. I have two others I can swap around to do testing, so wish me luck.

 

[TERRY WILL]

so I found the power door lock relay, does not look like the pics above at all. I tried to unplug it and it seems to be melted together. I did manage to get the cover off the two tiny solenoids that actuate the locks and I can watch them randomly lock and unlock the doors so it appears that there is stray voltage getting to them. Since the plug will not unplug I am suspicious that it may be right inside the plug. I will try to get the one out of my parts truck soon to see if it solves the problem. The wiring schematic above is not for the 1998. The 1998 has no BCM.

 

[TERRY WILL]

The 4x4 box was dead in the Suburban with the clicking, I swapped it out for one that I knew was good and now it is sending juice to the transfer case actuator witch make some noise but may not be engaging. I have a few spares if I can't get it working.

 

[TERRY WILL]

Cleaned up the points in the actuator and now it is working correctly.

 

[TERRY WILL]

the 4x4 issue is half fixed. When the transmission shop put the rebuilt tranny in they routed the wire harness that goes to the transfer case over the u joint which shredded the pug in. I bought used ends at the wrecking yard for $5 and wired them in. Now 4 high works perfect but 4 low still no go. I believe the motor is stuck, I am going to tear it down and fix it next. Any advice would be greatly appreciated.

 

[98Subdriver]

Nope, I have yet to find a solution. Chevy dealers service people seem to know less about this vehicle than I do, go figure. I've been told it is a body control module located near/behind the ash tray, probably burned or melted connections on circuit board. There is no mention of this BCM in my Haynes manual but one is shown in their wiring diagrams, but those show no locations. Good Luck! Please let us know if you find a solution...

 

[TERRY WILL]

So, I don't know what this thing is called, but it has two tiny solenoids with points attached inside. It is located just above the gas pedal, I tried to unplug it but instead the cover came off the inner workings. I cleaned up the points and re-attached the batter cable and everything seems to be working correctly now. It seems like the contact points were either sticking or not making good enough contact. It was hard to tell since it was up under the dash and my eyes aint exactly great up close. I Took one out of my parts suburban just just in case it was still giving me fits. The pics are of the location, and the one from my parts suburban.