"O/D off" light flashing intermittently (after 5.0 engine swap)

[RippinRangerFL2000]

Hey - I'm new to this forum and I have a small dilemma - would like to ask for advice & comments.

I have a 2000 Ranger XLT, which had a stock 3.0, auto, RWD. And, I just did an engine swap into this Ranger from a 1996 Explorer. I put in the V8 5.0 from the Explorer, along with the Auto transmission RWD, drive shaft and rear axle. It ran fine for the first couple of weeks, then the "O/D off" light began flashing intermittently, and transmission occasionally slipped. That quickly got worse and I basically destroyed the Transmission.

Luckily, another friend had a rebuild transmission (same 96 Explorer tranny), sold it to me, and we installed that… SAME problem of "O/D off" light flashing intermittently. I immediately took it to AAMCO and had them run the codes. Code was P1705, MLP sensor. I replaced the sensor, AAMCO adjusted the sensor.

SAME problem of "O/D off" light flashing intermittently. Now, I had an extra computer and swapped that, thinking maybe the computer was bad…SAME problem.
Next, I traced wires to see if there is a short or a bad connection somewhere. But, I didn't find anything.

Does anyone have any more advice…?
I'm running out of options. Am I overlooking something really obvious, here?
Thanks in advance!

 

[RippinRangerFL2000]

Hey - I'm new to this forum and I have a small dilemma - would like to ask for advice & comments. (I also posted this on the Transmission Forum).

I have a 2000 Ranger XLT, which had a stock 3.0, auto, RWD. And, I just did an engine swap into this Ranger from a 1996 Explorer. I put in the V8 5.0 from the Explorer, along with the Auto transmission RWD, drive shaft and rear axle. It ran fine for the first couple of weeks, then the "O/D off" light began flashing intermittently, and transmission occasionally slipped. That quickly got worse and I basically destroyed the Transmission.

Luckily, another friend had a rebuild transmission (same 96 Explorer tranny), sold it to me, and we installed that… SAME problem of "O/D off" light flashing intermittently. I immediately took it to AAMCO and had them run the codes. Code was P1705, MLP sensor. I replaced the sensor, AAMCO adjusted the sensor.

SAME problem of "O/D off" light flashing intermittently. Now, I had an extra computer and swapped that, thinking maybe the computer was bad…SAME problem.
Next, I traced wires to see if there is a short or a bad connection somewhere. But, I didn't find anything.

Does anyone have any more advice…?
I'm running out of options. Am I overlooking something really obvious, here?
Thanks in advance!

 

[Ranger850]

does it flash in a pattern. Like blink 3 times, pause, blink 3 times. or does it seem to be random? Usually the flash pattern is a code and can be deciphered

 

[RippinRangerFL2000]

Yeah, it does have a flash pattern. So, AAMCO ran the codes. Code was P1705, MLP sensor. And, I replaced the sensor, AAMCO adjusted the sensor. But, still had the same problem.
The computer is from the 1996 Explorer.

But, it seems like it may be something in the wiring where the gear selector is in the proper position, but the signal isn't going into the tranny quite right. Perhaps, the Ranger wiring harness is the problem. I may do some testing with a multimeter today. Any other suggestions?

 

[Dirtman]

What part of the ranger wiring harness is still in the truck?

I definitely thinks it's a wiring issue but not clear what parts of the ranger harness you are using vs the explorer harness.

 

[RippinRangerFL2000]

Thanks. By the way, the computer is from the 1996 Explorer.
Ranger: body harness. Explorer: engine/pcm/transmission harness

 

[Dirtman]

When doing these swaps it's easy to pinch a wire. I think your best bet is to do like you planned. Get a wiring diagram and go pin by pin and check ohms.

The digital range sensor/mlps is really important to trans function. I dont know why but the computer talks to it and sees a specific voltage. Something like 1.6 volts. If the voltage is off the computer can do all sorts of weird shit to the trans. I had a situation where my range sensor had failed and I got solenoid codes. I would verify that it was adjusted properly, all you need to do is look at the lines on the output shaft from the shift linkage and the range sensor. Each should have a mark and they should be perfectly aligned. Then get to testing wires from both the range sensor and main trans harness.

 

[RippinRangerFL2000]

Yeah, great suggestions, I had searched for a pinched wire, too - because, it sits pretty close to the firewall. I'll keep searching and also do the tedious testing of the wires.
Lmk if you can think of anything else.

 

[RippinRangerFL2000]

Thanks again -
So, I had to bring in my team of experts. I have the truck at my friend's shop because he has the testing equipment and software, (and, he's done a few 5.0 Ranger swaps).
And, I have a brother who has been a Ford mechanic for years.

Regarding your comments - you're spot-on!
Unfortunately, it didn't resolve the issue.
We've traced all of the wiring - and it's all good.
We installed another new MLP sensor, - and it has been adjusted.
So, now we're looking for something different.

The scanner is hooked up, it is in Park on the column, but the computer says its in 1st, for example.
That's what it shows when we test the MLPS with the scanner in Live Data mode.

Thinkin that we may be overlooking something obvious.
Hoping that you have the answer.

 

[Dirtman]

Has to be adjusted wrong, shift cable not set properly, or wiring to the range sensor is damaged. I can't think of anything else.

 

[RippinRangerFL2000]

Okay, thanks for the feedback. I'll let you know what I find.

 

[RippinRangerFL2000]

Problem was resolved by Joe Perri
BaySide Automotive
Address: 987 Withlacoochee St, Safety Harbor, FL 34695
Phone: (727) 223-8767
He'll post the details, soon.

 

[Dirtman]

Nice, I'd love to know what the issue was.

 

[Ranger850]

We have to wait for Aerosmith to get off tour first.

 

[Dirtman]

We have to wait for Aerosmith to get off tour first.