PCM - MIL ON/Multiple DTC's Set
Bulletin No.: 016/98Issued: 12/23/98
Revised:
Category
K (05)
Applicable Model/s
1997-99 B-Series
Subject
MIL ILLUMINATION WITH DTC'S P0705, P0708, P1704, AND/OR P1705
APPLICABLE MODEL(S)/VINS
All 1997-99 B-Series with automatic transmission.
DESCRIPTION
Diagnostic trouble codes (DTCs) P0705, P0708, P1704, and/or P1705 may be stored in memory. This may be caused by the Powertrain Control Module (PCM), wiring harness, connectors, and/or Digital Transmission Range sensor (DTRS).
Customers complaining of this concern should have their vehicle repaired using the following procedure.
REPAIR PROCEDURE
1. Verify customer complaint.
2. Connect the New Generation Star (NGS) tester to the vehicle and call Parameter Identification Displays (PIDs) TR, TR_D, and TR_V.
3. Move the shift lever into each gear and stop.
4. Observe the PIDs while wiggling the harness, tapping on the sensor, and/or driving the vehicle.
^ P0705- The computer saw a bit pattern which is not in the chart below.
^ P0708- The voltage for TR3A (displayed in TR_V) was higher than 1.8V.
^ P1704- The computer saw an in-between position when the test was initiated.
^ P1705- The computer did not see 0000 (P) or 0110 (N) when the test was initiated.
5. Compare the PIDs to the chart above.
^ TR_V is the voltage at PCM Pin 64 (TR3A circuit) to signal return.
^ TR_D: 1 = open DTR switch. 0= closed DTR switch.
^ Breakout box readings: Taken from PCM signal pins for TR1 TR2, TR3A, TR4 to signal return.
^ Voltages for TR1, TR2, and TR4:
-0 = 0.0 volts (circuit shorted to ground)
-1 = 9.0-14.0 volts (open circuit)
^ Voltages for TR3A:
-0 = 0.0 volts (circuit shorted to ground)
-1 = 1.3-1.8 volts (open circuit)
-1.8-5.0 volts = invalid reading (open in wires or bad resistor in DTR sensor).
Refer to Workshop Manual section 05 under Digital Transmission Range (DTR) Sensor for additional diagnostic procedures.
6. In addition to Workshop Manual procedures, the following tips are provided.
^ "In Between" readings could be caused by a shift cable or DTR sensor misalignment or a DTR circuit failure of TR1, TR2, TR3A, or TR4.
^ TR1, TR2, TR3A, and TR4 are all CLOSED in Park (shorted to signal return). Park is a good position to check for intermittent open circuits (with NGS monitoring TR_D).
^ TR1, TR2, TR3A, and TR4 are all open in Overdrive (O/D). O/D is a good position to check for shorts to ground. To determine the shorted component, unplug each connector while observing TR_D. If the short is in the PCM, remove the suspect circuit(s) wire terminal from the PCM connector. If the short still persists, then the PCM has an internal failure, otherwise the failure is in the vehicle harness.
7. Verify repair.