I have a 98 sport. 4.0L auto trans. a few times it has just died while going down the road. the only code i can get from the computer is P1694, which seems to be common and no one can tell me what it means. every once in a while it will have a rough idle or just not idle at all.

 

PCM is the engine computer. TCM is the transmission computer. Look for loose, dirty or corroded wire connectors. Inspect for damaged, broken, or short circuited wires. Carefully disconnect all the wires plugs you can find and inspect them. Use some electrical contact cleaner on the plugs and firmly reconnect them.



DTC P1694 will set if no CCD bus messages are received from PCM for 20 seconds or invalid messages are received for 20 seconds.

Possible Causes
CCD Bus (-) circuit open between PCM and TCM.
CCD Bus (+) circuit open between PCM and TCM.
Transmission CCD bus wiring damaged.
Faulty TCM.

Diagnostic Procedure
1. Using scan tool, clear TCM DTCs. Start engine and let idle for at least 2 minutes. Using scan tool, retrieve TCM DTCs. If DTC P1694 returns, go to next step. If DTC P1694 does not return, go to step 5.

2. Check instrument cluster gauges for proper operation. If fuelgauge and speedometer operate properly, go to next step. If fuel gauge and speedometer do not operate properly, see appropriate INSTRUMENT PANELS article.

3. Turn ignition off. Disconnect Gray PCM harness connector. PCM is located at left front of engine compartment. Disconnect TCM harness connector. Measure resistance of CCD BUS (-) circuit (White/Black wire) between TCM harness connector and Gray PCM harness connector. If resistance is more than 5 ohms, repair open in CCd BUS (-) circuit (White/Black wire). If resistance is 5 ohms or less, go to next step.

4. Measure resistance of CCD BUS (+) circuit (Violet/Brown wire) between TCM harness connector and Gray PCM harness connector. If resistance is more than 5 ohms, repair open in CCd BUS (+) circuit (Violet/Brown wire). If resistance is 5 ohms or less, replace TCM.

5. Conditions necessary to set DTC P1694 are currently not present. Inspect related wiring and harness connectors. See WIRING DIAGRAMS. Repair as necessary. If no problem is found, check for broken, bent, backed-out or corroded terminal pins. Check for chafed, pierced or partially broken wires inside insulation. Repair as necessary.