door lock issues

[jimmi308]

I just recently purchased a 98 xlt 5.0 and I am having an issue with the power locks. the back doors and tailgate lock and unlock with key fob and switch in cargo area. but the door switch locks all doors but the front 2 . are the switches bad or are the lock solonoids bad... just looking for a starting point. thank you

 

[J_C]

I would start looking for frayed wires in the bundle that goes from the front fender to the drivers door, under the rubber surrounding them. They flex every time the door is opened and closed and subsequently break. It's a pain to pull aside to get clearance.

Switches you can check by pulling them and measuring continuity with a multimeter. Solenoids you can check using a jumper wire from the battery to energize them, but they seem the least likely culprit. You could also measure whether 12V is getting to them when the switch is pressed with a multimeter voltage measurement at each lock connector.

 

[jmvb]

When I bought mine, no one power lock work fine.

It should be noted that the truck was stopped 6 years.

After a lot of WD40 in the locks and in the inner links area, they began to work fine, gradually, even the tailgate power lock

Today all of them perform well. They was just rusty.

 

[jimmi308]

ill be looking into this on the weekend... Ill post any results I may get.. thanks for advice...

 

[bobflood]

Because the back locks work from tailgate switch and key fob, I would first look at a splice under the rear driver side door. Pull up the plastic trim at the bottom of the door opening. This is a very common problem; the rear stuff works because the RAP module and the door lock/unlock relays are in the back - drivers side in the cargo compartment. The door lock wiring is pink/yellow for lock and pink/light green for unlock. Good luck.

 

[jester1023]

I've been having this issue on the driver door only. When it's warm and dry, it fails. When it's rainy or cold, it works. I blasted the latch/lock mechanism with Break Free gun treatment and then followed it up with RemOil gun lube. I would have used PB Blaster, but it will break things loose, then it kind of gums back up. The odor of the other two products is much more pleasant than the Blaster as well.