Mechanics

JEEP CHEROKEE TRANSMISSION PROBLEM

1999 Jeep Cherokee

Transmission problem
1999 Jeep Cherokee V8 Four Wheel Drive Automatic

1999 jeep grand cherokee limited v8 4.7 liter. Two codes on computer first code is p0888 and second code is p0871 car only drives in 2nd and 3rd gear also has reverse.I started it up and shifted into gear quick and it started in first but then jumps to second or third and wont downshift when I put accelerator to the floor. Mainly starts out in 2nd or 3rd but if I start out quick a couple times it started out quick. Not sure if its a pressure sensor or solenoid because I already checked relay in distribution box.I also noticed some jeeps have a governor pressure solenoid as one unit but unsure if mine is seperate .I only see the transmission control solenoid listed at auto zone and it cost 130.I dont wanna replace it and not be the problem I believe its inside the transmission pan
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Southiekid
March 18, 2010.




18 Mar 2010/1800hrs

Hi southiekid, Welcome to 2carpros and TY for the donation

These 3-sensors coolant temperature, throttle position and vehicle speed gives the computer an input signals that indicates throttle pressure and governor pressure to command and control the upshift/downshift/overdrive by activating a given shift solenoids in the transmission. Sounds more like a problem within the valve body and shift solenoids-What you need to do here is get it pressure tested to find out more what's happening internally.

Rasmataz
Mar 19, 2010.
Like I said p0888 and p871 is the code, I couldve had someone tell me to see a mechanic for free. You guys are a real disappointment.I didnt get a code for a coolant sensor or the speed sensor although I know the speed sensor could cause the program but thanks for the useless advice. If you got any real advice feel free to offer it.
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Tiny
Southiekid
Mar 20, 2010.
I gave you thoses sensors bcuz it has something to with the transmission operation-On the P0888 TCM power Relay Sense Circuit.

POSSIBLE CAUSES: INTERMITTENT WIRING AND CONNECTORS

FUSED B+ CIRCUIT OPEN

TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT OPEN

TRANSMISSION RELAY CONTROL CIRCUIT OPEN

TRANSMISSION CONTROL RELAY GROUND CIRCUIT OPEN

TRANSMISSION CONTROL RELAY STUCK OPEN

TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT SHORT TO GROUND

TRANSMISSION RELAY CONTROL CIRCUIT SHORT TO GROUND

TCM - TRANSMISSION CONTROL RELAY ALWAYS OFF

TCM SOFTWARE UPGRADE

You need to be patient here this is not a simple fix it requires extensive diagnostic to resolve the issue and I'm doing it over the internet compared to live-otherwise request your small donation

Rasmataz
Mar 21, 2010.
Do you know if the pressure sensor and the solenoid are two seperate pieces because I seen on some jeeps the governor pressure solenoid is all one piece.I only made a small donation because I gambled on your site and im not a big gambler if the payoff was big I would pay more

Tiny
Southiekid
Mar 21, 2010.
Do you know if the pressure sensor and the solenoid are two seperate pieces because I seen on some jeeps the governor pressure solenoid is all one piece


http://www.2carpros.com/forum/automotive_pictures/12900_gp_1.jpg


Rasmataz
Mar 21, 2010.
GOVERNOR PRESSURE SENSOR
NOTE: Governor pressure sensor may also be referred to as governor pressure transducer.

Governor pressure sensor delivers an output signal to the PCM indicating the output pressure of governor pressure solenoid. The PCM uses this signal to control governor pressure. Governor pressure solenoid is located on valve body.

GOVERNOR PRESSURE SOLENOID
Governor pressure solenoid generates governor pressure required for transmission upshifts and downshifts. Governor pressure solenoid is located on valve body. Inlet side of governor pressure solenoid is exposed to normal transmission line pressure and outlet side provides a passage to governor circuit in the valve body. Governor pressure solenoid regulates transmission line pressure to the governor circuit. Electrical supply voltage is supplied to governor pressure solenoid by PCM. The PCM controls the ground circuit to governor pressure solenoid to provide solenoid operation.

Rasmataz
Mar 21, 2010.
Thank you that was much more helpful sorry if I was rude in my earlier post but I have very little faith in most mechanical shops and even the honest ones seem to charge you up.

Tiny
Southiekid
Mar 21, 2010.
Thank you for using 2CarPros. Com. We appreciate your donation and look forward to helping you in the future.

Tiny
2CarPros Linsey
Mar 23, 2010.

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