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99 Jeep Grand Cherokee Laredo 4.7L P0988 & P0888 (Trans In Limp Mode)
Hello all, hopefully someone can help with this problem.
I have a Jeep Grand Cherokee Laredo 99 4.7L and the transmission is in Limp Mode.
I'll explain a little about my problem, after getting up to speed one day on the highway I felt a lunge from the vehicle. After the lunge the RPMs went up from maybe 1500 to 2200 and the check engine light came on. The vehicle feels sluggish and doesn't take off from a stop very well (have to give it more gas) I'm thinking perhaps it is stuck in 3rd gear. Once I was at home I used my OBDII reader to check the codes from the check engine light, and the codes it gave me are P0988 and P0888. I'm not sure where to look to first, I did poke around looking for broken wires/bad grounds. I didn't see anything really obvious though...
Any help would be appreciated, before I throw a part at this problem. :lol:
Last edit: 5 years 10 months ago by James200400. Reason: codes not in subject
Check for power on the red line after you find power on the green line (relay integrity) -- see image.
EDIT: Don't forget to check your ground too. Looks like on the Transmission Solenoid / TRS Assembly it's grounded on the case / housing so touch a test light connected to battery positive on the housing of that thing.
On the Transmission Control Module, check the BLK/YEL wires on pin 37, 39 and 57 for good constant ground there.
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