1. 2005 TJ Slips Out Of Gear

    My '05 TJ started slipping out of gear. It's an automatic. She has 130,000 miles.

    She's going through a wear cycle and has many codes:
    -----
    P0871 - Overdrive hydraulic pressure switch circuit.
    P2096 - Downstream post catalyst fuel trim system 1 lean. (TSB?)
    P2098 - Downstream post catalyst fuel trim system 2 lean. (TSB?)
    P0700 - Transmission malfunction present.
    P0871 - Transmission fluid pressure sensor / switch C circuit range / Performance (pending).
    -----

    I was working on 2096/2098 when the transmission slippage began.

    I changed the transmission fluid and filter, but there's no change.

    Maybe it's a common problem? I'm hoping someone here can assist by cluing me in on what to check etc.. I have fairly limited tools.

    I prefer to start with the simplest things first.. For instance, could it be a hole in a vacuum line or a loose sensor connection? I just don't know where to start looking!


    2005 TJ Slips Out Of Gear-20190612_165438.jpg
    I must go; for I am their leader, and they have gone.

  2. #2
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    First check your battery. Bad battery can throw many erroneous codes.

    Did you use the correct fluid and enough?


    Never look down on anyone unless you are helping them up - Jesse Jackson
    Last edited by JPNinPA; 08-13-2021 at 10:32 PM.
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  3. #3
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    Re: 2005 TJ Slips Out Of Gear

    Symptoms

    Symptoms of a P0871 include:

    Transmission overheating
    Slipping
    Failed gear engagement
    Causes

    Low transmission fluid level
    Dirty transmission fluid
    Transmission fluid leak
    Overheated transmission
    Overheated engine
    Damaged wiring and connectors
    Transmission pump failure
    Transmission fluid pressure sensor failure
    Transmission fluid temperature sensor failure
    Transmission control module failure
    Internal mechanical failure
    How to Diagnose the Code?

    One of the first steps to diagnosing a P0871 OBDII trouble code, is to check the manufacturers TSB database to see if there are any known solutions for this transmission problem. Next, the wiring and connectors leading to the TFPS sensor need to be inspected for signs of damage and corrosion. The transmission fluid pressure sensor will need to be tested as well, to determine if it is operating properly. If no issues are found up to this point, then an internal mechanical issue (most likely in the valve body) should be suspected.


    Never look down on anyone unless you are helping them up - Jesse Jackson
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  4. #4

    Re: 2005 TJ Slips Out Of Gear

    The battery has been replaced with the error present before and after.

    A shop did the fluid and filter change. I checked it using the correct procedure then, and I'm going to check it tomorrow too. I've read several posts of people slightly overfilling their ATF, so I was thinking of adding some this weekend (maybe).

    The fuses and relays all look good.

    In looking at the P0871, there's a TSB for it talkin' 'bout the connector getting corroded. I'm going to try to look at that tomorrow to see if I can get to it. I don't have the tools or jacks to lower the transfer case skid, so I may not be able to see it.

    Here is the TSB, although I don't know if it's the problem or not..
    21-009-05.pdf

    Other sites say damage and corrosion are common for this harness. Where Jeep recommends cutting back the wire and replacing the connector, others say that it can be cleaned. The issue is that I may not be able to get to it..


    Would there be any other things to check?

  5. #5
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    Quote Originally Posted by Pear View Post
    The battery has been replaced with the error present before and after.

    A shop did the fluid and filter change. I checked it using the correct procedure then, and I'm going to check it tomorrow too. I've read several posts of people slightly overfilling their ATF, so I was thinking of adding some this weekend (maybe).

    The fuses and relays all look good.

    In looking at the P0871, there's a TSB for it talkin' 'bout the connector getting corroded. I'm going to try to look at that tomorrow to see if I can get to it. I don't have the tools or jacks to lower the transfer case skid, so I may not be able to see it.

    Here is the TSB, although I don't know if it's the problem or not..
    21-009-05.pdf

    Other sites say damage and corrosion are common for this harness. Where Jeep recommends cutting back the wire and replacing the connector, others say that it can be cleaned. The issue is that I may not be able to get to it..


    Would there be any other things to check?
    What do you mean "look good"? When assessing fuses and relays.

    In the TSB the only Symptom is the code. At a minimum the wiring can cause issue. The inspection seems simple enough. Look for corrosion.
    Though without tools this may present an issue.


    There is a note in the TSB that this may be reimbursable under warranty. So you might a
    Call jeep and check if they will repair under that warranty.

    Regards,
    JPNinPA

    Never look down on anybody unless you're helping them up. -Jesse Jackson
    Last edited by JPNinPA; 08-18-2021 at 10:08 AM.
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  6. #6

    Re: 2005 TJ Slips Out Of Gear

    Quote Originally Posted by JPNinPA View Post
    What do you mean "look good"? When assessing fuses and relays.
    While looking for a TSB on P0871 as the article you mentioned suggested, I found this info about checking the wiring starting with the transmission fuses and relays (at the bottom of this post).
    P0871 Error Code | Jeep Wrangler TJ Forum
    What I mean by "look good" is that fuses weren't busted and the relays had clean connections.

    Quote Originally Posted by JPNinPA View Post
    In the TSB the only Symptom is the code. At a minimum the wiring can cause issue. The inspection seems simple enough. Look for corrosion.
    Though without tools this may present an issue.
    That's what I'm doing now.

    Quote Originally Posted by JPNinPA View Post
    There is a note in the TSB that this may be reimbursable under warranty. So you might a
    Call jeep and check if they will repair under that warranty.
    I'm the second owner and she's 16 years old (I've had her 12 of those years :)). I didn't think they covered stuff under warranty that far out and for a second owner.


    Edit to add:
    I checked to see if I could get to the connector from under the Jeep and I can't (tsb mentions lowering the transmission by up to 4" to get to it). Not sure what to check next.
    Last edited by Pear; 08-18-2021 at 04:54 PM.

  7. #7

    Re: 2005 TJ Slips Out Of Gear

    I didn't think they covered stuff under warranty that far out and for a second owner.

    24 yrs ago I bought a 7 yr old jeep cherokee. I had it about 6 months and there was a brake rotor recall at which time the service dept found an unrepaired transmission cable recall which they also did - all free of charge. While some recalls have time limits, it's always worth checking into.

  8. #8
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    Ok the fuses are good. Besides visual some use a multimeter. You could check for voltage on both sides or continuity.

    The relay you might try swapping it with another. Id have to check if they are the same but swapping with the horn will give quick feed back.


    As mark sr noted some TSBs are safety related (recall) and have no expiration.

    Never look down on anyone unless you are helping them up - Jesse Jackson
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  9. #9

    Re: 2005 TJ Slips Out Of Gear

    Quote Originally Posted by JPNinPA View Post
    The relay you might try swapping it with another. Id have to check if they are the same but swapping with the horn will give quick feed back.
    That's a neat hack, I'll have to remember that!


    Quote Originally Posted by mark sr View Post
    ..which they also did - all free of charge. While some recalls have time limits, it's always worth checking into.
    Quote Originally Posted by JPNinPA View Post
    ..some TSBs are safety related (recall) and have no expiration.
    I see, I didn't know that. I'll have to check with them!

    I reset the brain somewhat recently, so the check engine light isn't lit. I'm assuming I'd need to drive it a bit to regenerate the codes before I take it in?

  10. #10
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    Yes or the codes are not real.

    I cannot express enough how a bad battery or connection can cause many odd issues and codes.

    The battery wires themselves can be corroded. The connectors and the connection locations The ground from battery to engine or battery to chassis needs to be less than 2 ohms or you will see issues. The contact areas clean along with the connectors.
    Look at these things annually.

    Get the battery load tested.occasionally.


    Never look down on anyone unless you are helping them up - Jesse Jackson
    Last edited by JPNinPA; 08-19-2021 at 03:20 PM.
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  11. #11

    Re: 2005 TJ Slips Out Of Gear

    Quote Originally Posted by JPNinPA View Post
    I cannot express enough how a bad battery or connection can cause many odd issues and codes.
    Well, the battery was giving me problems not long ago. The 02 sensor ODB codes existed at that time, but not the slipping out of gear codes.

    It was acting like it wouldn't charge. I replaced the battery. I also replaced the PCM (didn't fix, so returned it) and the alternator. Like I said, it's going through a wear cycle so all kinds of stuff has been going wrong all at once (fuel pump, water pump etc)..

    I'm not 100% sure the new battery and alternator solved the charging problem. After the slipping out of gear issue, I haven't been driving it. I keep the battery fully charged with a battery maintainer but I don't know if it's charging while driving.


    ..I'd love to look into the battery connections. I have a multimeter. I'm not sure what I'd be looking at though. Can you explain what connections to check or point me to a website with step by step instructions / pictures?

  12. #12
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    Re: 2005 TJ Slips Out Of Gear

    Ill look for a website or video.
    Start with the ground lead. Is the battery post corroated? Polish it to a shine. Same with the ground connector. Inspect the wires from the cable into the terminal connector. Do they look corroded, fragile or broken? If so replace the cable. Follow the ground cable. It splits to the engine and chassis. At the engine disconnect and clean and lightly sand to a shine both the engine and wire end. Reconnect and tighten. Do the same for the chassis side.
    Inspect the wires at those ends.

    Then do the same for the positive side.


    Never look down on anyone unless you are helping them up - Jesse Jackson
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  13. #13

    Re: 2005 TJ Slips Out Of Gear

    Ok - I'll try that. This weekend is busy, so it may be a minute.. Thanks for your help btw.

    Will this inspection require disconnecting the battery? If so, will that reset the error codes I'm trying to capture?

  14. #14
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    Yep
    But if that is the cause. It will be worth it.

    Never look down on anyone unless you are helping them up - Jesse Jackson
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  15. #15

    Re: 2005 TJ Slips Out Of Gear

    and if its not, they will come back after a while
    99 xj with 350k miles on it. Still runs great

  16. #16

    Re: 2005 TJ Slips Out Of Gear

    Updating the thread..

    The battery cables looked good in a cursory check.

    The ATF was low when I checked again, it was full before so I must have a leak. I can't find the leak, so it could be blow-back and not leaving a trace.

    I'm going to check with a shop on the issues from here, thanks again to all for helping!

  17. #17
    Join Date
    Feb 2009
    Location
    Dayton Ohio Area
    Posts
    6,184

    2005 TJ Slips Out Of Gear

    Inspect for leaks from the bottom the radiator back to the yolk. Any thin oily fluid is suspect. What color is your transmission fluid?

    There is always a trace. Just have to find it.


    Never look down on anyone unless you are helping them up - Jesse Jackson
    "Never look down on anybody unless you're helping him up" - Jesse Jackson

  18. #18

    Re: 2005 TJ Slips Out Of Gear

    At least you know why it's slipping. Now is the riding part and you will be good again. At least you know it's not the transmission
    99 xj with 350k miles on it. Still runs great

Similar Threads

  1. Replies: 4
    Last Post: 05-01-2021, 12:32 PM
  2. 1998 ZJ PRND loose/Slips
    By andypw22 in forum Cherokee, Commander, Wagoneer and Liberty
    Replies: 2
    Last Post: 09-21-2010, 08:30 AM
  3. Gear Swap 2005 TJ Unlimited
    By red26 in forum Wrangler and CJ
    Replies: 9
    Last Post: 09-11-2010, 06:13 AM
  4. 94 YJ Makes noise and slips front in 4WD
    By mc355ss in forum Wrangler and CJ
    Replies: 8
    Last Post: 02-26-2009, 08:50 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Log in

Log in