1999 Ford Explorer Driver Door Lock

TEST A: ONE POWER DOOR LOCK INOPERATIVE
Manually operate inoperative door lock and check for binding or sticking lock. If door lock is not binding or sticking, go to next step. If door lock is binding or sticking, repair as necessary and recheck system operation.
Remove door trim panel and disconnect suspect door lock actuator connector. Using DVOM, measure voltage between ground and suspect door lock actuator connector terminal No. 1 (Pink/Black wire). Press door lock switch to LOCK position. If reading is 10 volts or greater, go to next step. If reading is less than 10 volts, repair open or short to ground in Pink/Black wire. See WIRING DIAGRAMS. Recheck system operation.
Measure voltage between ground and appropriate door lock actuator connector terminal No. 2 (Pink/Orange wire). Press door lock switch to UNLOCK position. If reading is 10 volts or greater, replace suspect door lock actuator. See DOOR LOCK ACTUATOR under REMOVAL & INSTALLATION. If reading is less than 10 volts, repair open or short to ground in Pink/Orange wire. See WIRING DIAGRAMS. Recheck system operation.

The power lock issue is likely bad wiring of the alarm, very common and one of the reasons shops hate any add-on's like them. One of the first things to check will be that wiring. Installers love to use scotch lock connectors to tap into wires and those cut the wires insulation so moisture gets in and corrodes the wires off. There are even ones who just bare the wires and twist them together with a wire nut. So find the alarm box and follow the wires. Look up the model number and you should be able to find a wiring diagram for it.

For the blower resistor. If you have the manual heater controls it is in the heater plenum right next to the blower motor. The automatic heat unit is in the back of the dash in the middle.

Glad we can help, please use 2Carpros anytime.

Best, Ken

Check the fuses. Replace if needed

Do you hear a clicking sound when you try to open the hatch electrically? Can you get the hatch to open with the key?

This may sound a little weird, but one time I had a hatch that would not open with the key or electric opener. I kept working the hatch until it opened, what I found that was causing my problem was a miss placed screw that had fallen down into the latch.

First, electrically, all the door locks operate off the same circuit, so that if one door unlocks electrically, then they all should work.
But as you stated, it doesn't sound like an electrical problem.

Second, when you insert the key, does it turn? If it turns, it looks like there might be a linkage problem. You will need to open the door panel to investigate the problem.

You might want to invest in a repair manual available from your local auto parts store. The "Haynes" manual I have has some photos and diagrams of the liftgate panel removal and the locking mechanism and instructions on removing the panel and lock.

My "Chilton" manual does NOT have any diagrams of the liftgate assembly.

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