jlschneck

I have a 1998 Cherokee Sport 4.0 4WD with the AW4 automatic transmission. Current mileage is around 183,000. My primary question is in regards to resetting the PCM and clearing DTC’s as well as the CEL. Here is some background information on the issue.Back in February I was experiencing unusually high idle with erratic throttle response. The CEL came on but the only code present via my cheap Amazon scanner was P0301 cylinder #1 misfire. My neighbor is a former mechanic and was able to determine via his high tech computer scanner that the issue was related to a faulty TPS. I went ahead and replaced with a new aftermarket TPS. We cleared the code with his scanner and the issue was resolved. Shortly after the CEL came back on. This time I was getting the P0301 cylinder #1 misfire trouble code as well as P0740 torque converter clutch lock-up system failure (TCC Solenoid). I did not experience any noticeable misfire and the transmission appeared to be working properly shifting between all gears as well as OD. I was able to clear the codes with my scanner. The CEL and these trouble codes have been occurring intermittently since March, again without any noticeable performance issues other than slightly lower than average fuel mileage at around 12 MPG. After researching similar issues on the forum it appeared the issue may be related to the aftermarket TPS. I decided to purchase a Mopar TPS and complete a voltage test of both parts by backprobing the connector as detailed in the TPS Testing I found on the forum. There were voltage differences between the two parts for the TPS Signal test (PIN 2). The aftermarket TPS was slightly above the allowable range at .96 volts and the Mopar TPS was within range at .83 volts. Based on this I decided to install the Mopar TPS. After installation I wanted to reset the PCM Adaptive Memory and clear the trouble code and CEL to see if the Mopar TPS resolved the problem. I did the PCM reset per the instructions I also found on the forum. Disconnect positive terminal from the battery and ground to the AC compressor for 30 seconds or so. Reconnect the cable and perform the following steps: Key ON, Headlights ON, Headlights off, Key Off. This did not appear to do anything as the CEL was still on and both trouble codes present when I read the system with my scanner. I was also not able to clear the codes or CEL with my scanner. I am receiving an “Erase Fail!” message from the scanner.Am I doing something wrong? Do I need to disconnect the battery over night to reset the PCM and clear the codes? Is something possibly wrong with the PCM?Any guidance and help would be very much appreciated.

jlschneck

I realized I may provided too much information rather than just pose the question at hand. Here is my issue. I am unable to clear my Jeep's CEL or erase/reset the fault codes. I have attempted to do this using my OBDII scanner as well as by resetting the PCM via the following method: Disconnect the positive battery cable and ground to the AC compressor for at least 30 seconds. Reconnect the positive battery cable. Turn the key on, turn headlights on, turn headlights off, turn key off.Neither method turns the CEL off or clears the fault codes. Keep in mind I am doing these after I believe to have fixed the problem that is causing the CEL and fault codes.Any ideas why I can not get my CEL to turn off and the fault codes to clear?

Far59

Did anyone ever get back to you, or did you figure it out, im having same problem ?