Transmission Codes P0700 & P0740

[ProgHouseDJ]

Hello!

I had codes p0700 and p0740 pop up a little while ago. So far, I have changed the input speed sensor, changed the transmission fluid and filter, added shudder stop, and changed the TPS sensor. I don't see any noticeable issues with function of the transmission- driving seems fine. The codes are still returning. What would the next step in troubleshooting this problem be?

Thanks!

 

[hear]

The P0740 is the torque converter lockup code. It sounds like you have a 42RLE (you mentioned input speed sensor), usually the fix involves replacing the solenoid on the valve body. But if it's shuddering, I would start by just disconnecting it. That's easy on the 32RH, but probably not possible on the 42RLE.

Also, fill out your profile so we know what you've got.

 

[ProgHouseDJ]

The P0740 is the torque converter lockup code. It sounds like you have a 42RLE (you mentioned input speed sensor), usually the fix involves replacing the solenoid on the valve body. But if it's shuddering, I would start by just disconnecting it. That's easy on the 32RH, but probably not possible on the 42RLE.

Also, fill out your profile so we know what you've got.

Yes it is a 42RLE. 2005 Wrangler Sport 4.0 Automatic. I don't notice any shuddering that wasnt there before. Usually a little bit of vibration when its above 55 MPH, but I attributed that to the lack of aerodynamics.

 

[ProgHouseDJ]

Is this the correct solenoid to address that issue?

https://transpartsnow.com/mopar-factory-42rle-solenoid-pack-04800171aa/

 

[hear]

Yes it is a 42RLE. 2005 Wrangler Sport 4.0 Automatic. I don't notice any shuddering that wasnt there before. Usually a little bit of vibration when its above 55 MPH, but I attributed that to the lack of aerodynamics.

Vibration over 55 is probably not transmission. Bad pinion angle, out of balance tires, or a bunch of other potential causes.

But I see now you didn’t say it was shuddering, but that you added shudder stop.

Also, il need a 42RLE Expert to chime in on the solenoid replacement.

 

[macleanflood]

Aren't most transmission issues in '05-'06 Wranglers the PCM?

Do you still have your original PCM?

@Wranglerfix can test your PCM. Www.wranglerfix.com

-Mac

 

[Wranglerfix]

How is your shifting from first to second when cold? How is the idle when hot?

 

[ProgHouseDJ]

How is your shifting from first to second when cold? How is the idle when hot?

The shift from first to second happens around 1800-2000 RPM, and seems to be pretty smooth. There isnt really any kind of delay before 2nd picks up. I dont notice anything strange at idle, maybe a tiny bit of something that sounds like surging? This is my daughters daily driver, so I haven't really put enough hours in it to get really familiar with how things sound.

 

[Wranglerfix]

You can send your pcm into us and we can test it for you just to be 100%. The symptoms that I described are (usually) what pops up but not always.

 

[ProgHouseDJ]

You can send your pcm into us and we can test it for you just to be 100%. The symptoms that I described are (usually) what pops up but not always.

What kind of things would I notice if there was an issue? Also could there be other electrical problems associated with failure? We did have an issue with some of the gauges not working all the time. Turning the ignition off then back on again usually corrects that. I assumed it was a contact problem with the gauge cluster.

Thanks!

 

[Wranglerfix]

Loss of gauges usually happens with the Manual Transmissions, but it has been known to happen with an automatic. Faulty O2 sensor codes, high transmission temperatures and a hard shift between first and second in the mornings are the usual suspects in an automatic.

 

[ProgHouseDJ]

A little update on this issue-

Tried a new PCM, and the problem persisted. Took it to a shop and had the shift solenoid pack replaced. The p0740 code went away, but 2 new ones came back in its place- away from home right now so I cant verify, but Im pretty sure it was 0750 and 0760. The jeep would not shift from 3rd to 4th gear. I disconnected the battery and let that reset, after which everything ran completely fine, until the error codes returned and then it was stuck back in 3rd gear.

The transmission shop owner is convinced it is an electrical issue somewhere, and judging by the condition of some of the wires underneath, and the evidence of water exposure under there is seems to make sense. I'm fairly certain I am going to end up selling the Jeep at this point, as it is my daughters daily driver and she needs something a little more fuel efficient, just trying to decide if its going to be worth trying to get it repaired or just sell as is.

Does anyone have any ideas? also, with the current issues does anyone have an idea of what may be a good asking price for it? 6cyl Wrangler Sport, soft top, 150k miles, surface rust on some of the frame but the body is solid, its been well maintained since I got it 4 years ago.

 

[hear]

if it won't shift into 4th, are you sure the overdrive defeat switch isn't enabled or shorted out somewhere? Otherwise the shifts are controlled by the TCM externally, and then internally via solenoids. My best guess would be that you have a bad solenoid, but that's just my armchair diagnosis. Computer problems are always a wildcard, and I tend to assume it's not the computer until I can prove that it isn't anything else.

 

[ProgHouseDJ]

if it won't shift into 4th, are you sure the overdrive defeat switch isn't enabled or shorted out somewhere? Otherwise the shifts are controlled by the TCM externally, and then internally via solenoids. My best guess would be that you have a bad solenoid, but that's just my armchair diagnosis. Computer problems are always a wildcard, and I tend to assume it's not the computer until I can prove that it isn't anything else.

Solenoids were just replaced- and if one were bad, it would probably still malfunction if I reset the computer, correct?

 

[ProgHouseDJ]

Solenoids were just replaced- and it runs just fine after resetting the codes- until the codes kick back in

 

[Rickyd]

A little update on this issue-

Tried a new PCM, and the problem persisted. Took it to a shop and had the shift solenoid pack replaced. The p0740 code went away, but 2 new ones came back in its place- away from home right now so I cant verify, but Im pretty sure it was 0750 and 0760. The jeep would not shift from 3rd to 4th gear. I disconnected the battery and let that reset, after which everything ran completely fine, until the error codes returned and then it was stuck back in 3rd gear.

The transmission shop owner is convinced it is an electrical issue somewhere, and judging by the condition of some of the wires underneath, and the evidence of water exposure under there is seems to make sense. I'm fairly certain I am going to end up selling the Jeep at this point, as it is my daughters daily driver and she needs something a little more fuel efficient, just trying to decide if its going to be worth trying to get it repaired or just sell as is.

Does anyone have any ideas? also, with the current issues does anyone have an idea of what may be a good asking price for it? 6cyl Wrangler Sport, soft top, 150k miles, surface rust on some of the frame but the body is solid, its been well maintained since I got it 4 years ago.

View attachment 580732

Whose pcm? Wranglerfix is the only company that fixes the 05-06 issues

 

[ProgHouseDJ]

Aren't most transmission issues in '05-'06 Wranglers the PCM?

Do you still have your original PCM?

@Wranglerfix can test your PCM. Www.wranglerfix.com

-Mac

It was a Wranglerfix PCM

 

[AndyG]

You have to be hyper diligent checking the harness- like rub wires with your fingers for nicks. Its a known where it runs up to the pcm it can rub as well.

Go deep.

 

[ProgHouseDJ]

You have to be hyper diligent checking the harness- like rub wires with your fingers for nicks. Its a known where it runs up to the pcm it can rub as well.

Go deep.

Would replacing the entire wiring harness be easier than trying to trace out the problems?

 

[macleanflood]

IMHO no... because there are no "new" wiring harnesses. You'd just be purchasing a used harness and it might have a different set of issues.

By the time you spend the money and wait for something to arrive you could simply deloom the harness and physically inspect and test with a multimeter and probably be done with everything by the time another harness showed up.

-Mac