1995 Explorer in 4-High for 10 miles on pavement!

[slsnut]

Thanks Gents for the feedback here. On the way back from the course I put the Explorer on a dirt farm road and tried 4 Auto on the fly. One or two seconds after the FWD light came on and it engaged!. After running 100 yards I brought it to a stop and switched it to 4 Low and was unsure if it went into Low range. Switched it back and light went off. Tried it again and it worked in 4 Auto but unsure if Low range engaged, I'm thinking not since when I used it before it was VERY clear I was in low. Shouldn't another light come on with low range? I remember seeing 2 lights when they were flashing, but that has quit since I was able to engage 4 Auto.

 

[Mbrooks420]

There is a light for low. It’s fairly audible, and it’s obvious when you are geared lower. That is likely to be a sticky motor. You can pull them and clean the dried grease out and get them working a fair amount of the time.

 

[slsnut]

Yup I saw the light for low range on start up. To be clear, which motor are you referring to? The one on the back of the T-case?

 

[Mbrooks420]

Yes. If you pull the motor you can shift it manually with a large set of pliers for testing.

 

[slsnut]

Gotcha, will have to do that in a few weeks after I return from from trip to Denver. Will report back then and thanks!

 

[slsnut]

Ok we returned from Denver after 3000 miles with the same symptoms, the FWD,FWD Low and the Door Ajar (red) light on far left of panel flashed continuously on start up continuing for sometimes 5-10 minutes before stopping and the OD off light flashes continuously when the engine is on. The Electronic vacuum control valve by the passenger headlight clicks and power windows start and stop when actuated in time with the flashing 4WD lights, and mileage was 17 MPG not the usual 19-20 MPG. 4WD system does operate when lights are not flashing.

 

[slsnut]

I should also mention that last week I replaced the PCM, and on start up the 4WD/4LOW and the Door Ajar lights began to flash again but the OD off light stayed off for 15-20 minutes of driving then returned to constant flashing. I verified today that the vehicle will go into 4WD when the lights quit flashing. Shift motor and vacuum control valve are audible and the lights that correspond to each setting work properly.

 

[Mbrooks420]

Do the interior lights come on when the door ajar lights flash?

 

[slsnut]

Yes they do as does the under hood light and the door open bell. Also I notice that there is some hesitation while accelerating at lower speeds. I am guessing this is a sensor giving the PCM some sort of out of range signal which puts it into limp home mode. My OBD I Ford reader now will not even scan for codes.

 

[slsnut]

Ok folks got this problem solved!. Traced to GEM (Generic Electronic Module) left of radio attached to dash superstructure with a single 7mm screw. After studying the Ford shop manual, it became clear that most of the connections into and out of the GEM in four multi-pin connectors were associated with all the systems which were malfunctioning I.E. FWD shift motor and sensors, electric windows, dome and courtesy lights, door ajar chime and dash lights, rear window defogger, coil circuit etc.

These malfunctions were severe enough to activate the "limp home" mode whereby the OBC puts the power train in a basic operating protocol which protects the vehicles critical systems until the malfunction is cleared. This mode is manifested by a continuously blinking O/D light. Pictured is the GEM which I replaced with a used unit on EBay for $31 and my factory manual I used to diagnose this issue. I also replaced the OBC (another Ebay $35 part) which did not fix the issue prompting me to try the GEM. My sincere thanks to all of you who helped me get this problem in hand!