1999 Explorer not shifting into 4th/overdrive

[JohnC910]

I recently acquired a new(to me) Explorer and as most older vehicles do, there were some problems with it, so when I was trying to diagnose why the vehicle will ding shortly after starting to drive the vehicle, I disconnected the battery hoping to reset the computer and in doing so I created a new problem. Ever since I have done that, the thing wont shift out of 3rd gear. 1-3 are fine and so is the reverse. I took it to an auto parts store and had a scan tool put on it and the only thing that stood out to me was 2 codes for a front right and rear center wheel censor. Is it possible that this could be my issue? I don't know if these will effect the way that the transmission shifts. My theory is that someone went in with advanced tools and disabled the sensors in the computer before selling it, but upon disconnecting the battery, they were restored to what they should be. Does anyone have any ideas?

 

[manimal]

Rear center? What are the actual codes? Does the speedometer work?

 

[CDW6212R]

ABS sensors, right and rear. The front ABS sensors are sealed inside the 4WD hubs, so that would likely be fine(wiring issue), or the hub bearings are bad.

The one on the diff, it's used for all speed and ABS functions, plus the transmission. I'd look there and be sure its intact without any damage to wires or connectors. If you find something odd, that might be the issue, it sounds like the VSS signal(rear ABS sensor) is not properly reaching the trans.

The VSS is routed through the ABS module first, then to the PCM, speedometer, and trans.

 

[drdoom]

FYI parts house scanners sometimes won't read Ford transmission codes. Have you tried addressing the speed sensor issue?

 

[manimal]

As for the ding noises, do they return after several minutes of driving?

There is a common issue with these vehicles where the airbag warning lamp in the dash fails. As part of the airbag test procedure the GEM self tests the airbag lamp, and will chime the dash bell if it senses that the airbag warning lamp has failed.

If you do not see the airbag lamp light up in your dash when you turn the key to the on position, this is probably your ding issue.

I believe the airbag warning lamp is an LED, you may need to pull the dash and check solder joints on it.

 

[JohnC910]

Manimal, the speedometer works fine, and as for the codes, the guy from the parts store didn't give me the codes, just the actual error. I was worried about him because after asking what year my vehicle was he proceeded to ask if it was OBD I or OBD II. The codes were actually front right and center, not rear center as I said earlier. The dinging will sometimes return but without any warning and with no particular reason. It will always happen in the first few minutes of driving and them sometimes at random increments further along. I will definitely check that light, and as for the speed sensors I think I am going to replace them, I just wasn't sure as to if that could actually cause my problem or not so that was part of the reason I posted here. They need to be replaced regardless but if I still would need a tranny rebuild, I will likely just sell the vehicle because I don't see the worth in putting a new tranny in a vehicle with 210,000 miles on it.

 

[Turdle]

Need to get the actual codes please.
Also, are you sure it is 4th gear missing, or are you missing torque converter lockup? T/C lockup feels like an up-shift. Both will result in high cruise speed RPM's


To find out-get up to 60 mph and push the OD off button. if the rpm's jump it was in overdrive (4th gear) without T/C lockup. Tc lockup can be effected by a lot of things-speed sensor being one. On your truck the rear speed-ABS sensor is on top of the rear diff pumpkin. You might check the wiring.

 

[manimal]

Yes that is consistent with the airbag lamp failure.

Have had family members with a 2000 Ex and 2002 F150 with the same issue. Unfortunately neither one repaired theirs, they just lived with the intermittent chimes.

Check the wiring on the front sensors, and clean the connectors at the hubs. Unfortunately to replace them the whole hub assemblies must be replaced.

At 200k I had one front bearing start to roar. They are so easy to replace that I just replaced both of them with NAPA Pro hubs. If you wait for one of their bucket sales you can fit both of the hubs in one of those 5 gal buckets and get 20% off.

 

[koda2000]

Regarding the air bag sensors, my '00 Mountaineer will occasionally flash the air bag warning light. Typically it will flash one of 2 sequences. 3-6 or 3-7. 3-6 is the drivers side and 3-7 is the passenger side. There's a yellow wire connector located on the rear, bottom center of each of the front seats. The wires are terminated with a resistor at that point. IDK if they were intended for side air bags or what, but I've never seen them go anywhere in an Gen II. Anyway, what seems to happen is that the resistor makes a poor connection sometimes (maybe someone kicks the wire?). If I pull and push on the connector a couple of times it will turn off the air bag warning light and all will be normal again. Does your airbag light come on during bulb check?

BTW, trying to get the ABS sensors out of the front hubs can be hard to do because of rust. I'm not even sure if they can be removed. They always come installed inside new hubs.Try cleaning them and the reluctor wheel and check the wiring first. The rear center one isn't too bad.

 

[Flash]

My speedo isn't connected because I've got a '99 transfer case in a '97 body so my transmission isn't getting signals to change properly.

When it hangs up on a gear I just snick the gear selector down one until it changes then go back up again.

You could try that until you fix yours properly.