4r100, O/D light blinking, no/low power
 

Truck:
2000 F250 XLT A/T 6.8L v10 4x4

Issue:
O/D off light is flashing on the shift lever. In a drive gear (R, OD, D2, D1) there is very low power when giving it gas, more so from a stop. In P and N, I can rev the motor with no obvious issues. In O/D, I can't even get forward momentum going from a stop when on a slight incline. When on flat ground and in O/D, flooring the gas only gets me going a few MPH and RPMs don't go above 1500ish. When selecting 1st or 2nd, the truck still struggles a bit from a stop but does get up and going.

What happened leading up to the issue:
I was on the freeway driving about 80MPH without cruise control se,t and with O/D on as usual, when the blinking O/D off light caught my attention. Not knowing at the time that this was a transmission problem light, I started pushing and holding on the O/D on/off button to try and get it to stop. Probably about a minute later, I realized I was losing speed even when giving more throttle so pulled over to the shoulder. I shut the truck off and restarted it, noted the Service Engine Soon light was now on, then I put it in O/D and gave it gas but only got going a couple MPH which it sounds like the engine was choking/struggling. I then tried D1 and D2 and, while still struggling a bit from stop, was able to accelerate up to 35+ MPH.


OBDII Codes:
P0743
Torque Converter
Clutch Solenoid
Circuit Electrical

P0750
Shift Solenoid A

P0755
Shift Solenoid B

P1747
Pressure Control
Solenoid A Short Circuit

P0443
EvaPorative Emission
System Purge Control
Valve Circuit

P0135
O2 Heater Circuit
(Bank 1. Sensor 1)

P0155
O2 Heater Circuit
(Bank 2. Sensor 1)


Troubleshooting:

1. Transmission fluid check looks good (full and red)
2. Checked fuse 23 of the Central Junction Box
3. Held a ground wire to botton of Transmission pan and to the frame while I started the truck, O/D light still flashing
4. Wiring looks good coming to the plug on the driver side of the transmission

More info:
- No "Service Engine Soon" or blinking O/D off light prior to all this happening.
- I don't believe I'm getting 1st gear. I don't recall if I got my speed up to 30+ MPH while in D1, but while in D2 I never noticed a shift from stop to ~35MPH. At 35MPH, my RPMs were around 2500 I believe.
- While cruising at 35MPH in D2, shifting to O/D results in lost power. I had to stay in D2 all the way home.

To do (I believe):
1. Check shift solenoids (looking for DIY info)
2. Check shift solenoid pack (looking for DIY info)
3. Check TCC solenoid (looking for for DIY info)


I'll be browsing this forum for more tips, but in the meantime wanted to throw up a post with my specific symptoms in hopes of getting some feedback. I won't be diving too deep into this before giving in and taking to a shop but wanted to try and eliminate any of the "simple" things first.

Any links to posts/pages about how to check some of the specifics would be appreciated. It sounds like there are a couple shift solenoids to check as well as a solenoid pack (how best to check these out, I'm still looking for)?

Please identify the model year of your truck along with its specific model identification and installed engine....

Done. Edited my original post

Truck:
2000 F250 XLT A/T 6.8L v10

It is not any of the solenoids unless several failed at the same time. You have a wiring issue, that's why you have all electrical circuit failures. Somehow the wiring harness was damaged. You might find the problem if you trace the harness from the PCM near the brake booster to the transmission.

Thanks for the response.

Are there any how to's on checking it with a multimeter at the transmission end or something?

From what I can see of the plug at the transmission and the wiring sleeve or split loom, it looks good. Will give it another look.

I have the banks power pack to for whatever that's worth.

Banks ottomind module

On a 2000 SD, Fuse F7 in the BJB provides operating power to all the transmission solenoids, the heaters for the two upstream 02 sensors, and the CANP valve.

Check it.

If blown, the most common reason is for one the O2 sensor harnesses to be lying on either the exhaust or a front driveshaft if 4 X 4.

Did you fix this?
 

Hi,

I'm curious if you found a solution to this problem? I believe I have the identical issue to what you described. I have the heater circuit malfuction codes and shift solenoid a and b codes as well...

Dave

Blown fuse.
 

Just checked the fuses, and sure enough there was one blown. Swapped it out with a good one, and the problem is gone.

Fuse location
 

Where do you find the fuse and what all does this fuse operate because even in my manual I can't find what the fuse box lists as each fuse just the numbers of each fuse and what amperage goes in it

So I'm having the same problem and I'm stuck. 2000 F-250, xlt w/v-10 and the #7, 20 amp fuse is toast and as soon as it's replaced, it burns out the new fuse. I'm sure it's a wire short but can't find it. An help on where to look?

Codes:
P0743 torque converter clutch solenoid circuit electrical
P0750 shift solenoid A malfunction
P0755 shift solenoid B malfunction
P1747 Pressure control solenoid A short Circuit
P1754 Coast clutch solenoid circuit malfunction
P1760 el. Pressure control solenoid high input
P0443 evaporative emission system purge control valve circuit
P1451 evaporative emission system vent control Valve circuit malfunction
P0135 ox sensor heater bank 1 sensor 1
P0141 ox sensor heater circuit bank 1 sensor 2
P0155 oxygen sensor heater circuit bank 2 sensor 1
P1409 el vac regulator control circuit

See post #7.

First thing I checked was the wires and sensors around the exhaust and drive shafts. I've followed the harness as best I can to see if there were any areas of obvious arcing or where the plastic shielding was worn through but no luck. Just thought someone might have an idea of a not so obvious area to check?

Then you should have stated specifically what you had done.

Is this a California-specification (OBDII) vehicle? Check the label on the underside of the hood.

Unplug the transmission and every sensor or actuator for which a fault code is posted and see if the short goes away. If so, one of them is shorted and you'll have to plug them in one at a time to see which has the internal short. If the short still existed after unplugging everything, then it gets a lot harder as a harness has shorted to ground.

After a lot of head scratching I narrowed it down to the o2 sensor. I replaced the sensor and the #7, 20 amp fuse and the truck runs fine now! That was a pain for something so simple.