bigalpha
Moderator
- Location
- Tucson, AZ
1995 XJ, AW4
- When in 'D', the tranny defaults to 4th gear.
- I can drive it and manually change the gears from 1-2, 3, 4.
- 4th will downshift to 3rd if I goose the throttle.
- I can drive the Jeep with the computer unplugged.
- Replaced TPS with new - tested with meter; meets voltage guidelines.
- Jeep runs pretty smoothly, and does not stumble. Idles low every once in a while, I think it's vacuum related.
- Jeep in 'Park', ignition 'ON', TCM unplugged - Tested TCM connector - 'Power In' is satisfactory.
- Jeep in 'Park', ignition 'ON', TCM plugged in - C14-C16 registerd 0 ohms.
- I replaced the computer with a junkyard computer from a 95 XJ Sport; no change. No guarantee the computer was working.
- I checked all fuses and all are good (unless fuses go bad w/o actually blowing the fuse?)
- Wiring harness at the TCM is in good shape with no cuts or breaks in the wiring
- The ground at the TCM is grounded properly.
- Gauges seem to be working properly.
- No CEL.
- Before I replaced TPS, I pulled codes and it gave me "24: check TPS and wiring". After replacing the TPS, the code is gone.
At some point, there was some alarm system installed on the Jeep. I pulled the siren out the other day because it's not even hooked up anymore. By the fusebox, there is a tan/light brown wire with a black strip that has been cut. I have no idea what it goes to. It disappears into a bundle of wires taped together under the dash.
Fusebox:
Stray wire:
I believe that about sums up what I've done so far. I would LOVE to get this problem fixed; especially if it's a (relatively) cheap problem I can fix at home. I'm open to questions and comments. I can get better/new pictures of anything to help diagnose this problem.
Now for my questions:
1. If the solenoids were bad, the tranny would not shift, right?
2. What can cause C14-C16 inputs to not receive any input from the solenoids?
3. What are other troubleshooting steps I can do to narrow down my problem?
4. How can I diagnose a bad TCM?
5. If the TCM is dead and I replace it (and it fixes the problem) will the tranny start shifting properly immediately w/o disco the battery?
6. Assuming a sensor is at fault, and I replace the sensor, will the tranny start shifting properly immediately w/o disco the battery?
7. Can a fuse go bad w/o actually blowing?
- When in 'D', the tranny defaults to 4th gear.
- I can drive it and manually change the gears from 1-2, 3, 4.
- 4th will downshift to 3rd if I goose the throttle.
- I can drive the Jeep with the computer unplugged.
- Replaced TPS with new - tested with meter; meets voltage guidelines.
- Jeep runs pretty smoothly, and does not stumble. Idles low every once in a while, I think it's vacuum related.
- Jeep in 'Park', ignition 'ON', TCM unplugged - Tested TCM connector - 'Power In' is satisfactory.
- Jeep in 'Park', ignition 'ON', TCM plugged in - C14-C16 registerd 0 ohms.
- I replaced the computer with a junkyard computer from a 95 XJ Sport; no change. No guarantee the computer was working.
- I checked all fuses and all are good (unless fuses go bad w/o actually blowing the fuse?)
- Wiring harness at the TCM is in good shape with no cuts or breaks in the wiring
- The ground at the TCM is grounded properly.
- Gauges seem to be working properly.
- No CEL.
- Before I replaced TPS, I pulled codes and it gave me "24: check TPS and wiring". After replacing the TPS, the code is gone.
At some point, there was some alarm system installed on the Jeep. I pulled the siren out the other day because it's not even hooked up anymore. By the fusebox, there is a tan/light brown wire with a black strip that has been cut. I have no idea what it goes to. It disappears into a bundle of wires taped together under the dash.
Fusebox:
Stray wire:
I believe that about sums up what I've done so far. I would LOVE to get this problem fixed; especially if it's a (relatively) cheap problem I can fix at home. I'm open to questions and comments. I can get better/new pictures of anything to help diagnose this problem.
Now for my questions:
1. If the solenoids were bad, the tranny would not shift, right?
2. What can cause C14-C16 inputs to not receive any input from the solenoids?
3. What are other troubleshooting steps I can do to narrow down my problem?
4. How can I diagnose a bad TCM?
5. If the TCM is dead and I replace it (and it fixes the problem) will the tranny start shifting properly immediately w/o disco the battery?
6. Assuming a sensor is at fault, and I replace the sensor, will the tranny start shifting properly immediately w/o disco the battery?
7. Can a fuse go bad w/o actually blowing?