The transmission is not responding.
Troubleshooting:
The transmission is indicating that one of the following conditions exists:
Note: For transmissions that have the transmission pressure sensor mounted on the pump instead of the clutch pack, set the PCP configuration parameter "Transmission Neutral Pressure Limit" to zero psi in order to disable this diagnostic code.
- The transmission is in gear when the transmission is commanded to NEUTRAL.
- The transmission is not in gear when the transmission is commanded to operate AHEAD or ASTERN.
Note: This diagnostic code is generated in the PCP. The PCP uses the transmission pressure that is received from the Engine ECM through the J1939 Data Link in order to determine the alarm condition. The 8-pin cable provides the interface from the PCP to the transmission gear. A second cable is used with the various gears that can be used with Caterpillar Engines and the multi-station control system (MSCS).
Test Step 1. CHECK THE WIRING AND CONNECTORS.
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| Illustration 1 | g01030049 |
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(1) Power train Control Processor (PCP)
(2) 8-pin connector (PCP side) (3) 8-pin connector (transmission cable) (4) PCP transmission cable (5) 8-pin connector (transmission solenoids cable) (6) Cable for the transmission solenoids | |
- Turn the keyswitch OFF.
- Inspect the connections for the data link for the PCP to the ECM and also inspect the connections at the transmission solenoids.
- Check the harness and wiring for the following conditions:
- Corrosion
- Abrasion
- Pinch points
- Incorrect attachment
Expected Result:
All harnesses are in good condition.
Results:
- OK - All harnesses are in good condition. Proceed to Test Step 2.
- NOT OK - All harnesses ARE NOT in good condition.
Repair: Repair the harnesses or replace the harnesses.
Recheck all of the harnesses. Ensure that the harnesses are in good condition.
STOP
Test Step 2. MEASURE THE RESISTANCE THROUGH THE PCP TRANSMISSION CABLE. (SHORT CIRCUIT TEST)
- Turn the keyswitch OFF.
- Disconnect the PCP transmission cable (4) from the PCP (1).
Refer to Illustration 1.
- Disconnect the cable for the transmission solenoids (6) from the PCP transmission cable (4).
- Measure the resistance between pin 1 (+V FWD) and pin 8 (−V FWD) on the 8-pin connector (3) for PCP. Wiggle the harness during a measurement in order to reveal an intermittent condition.
Show/hide table
Illustration 2 g01678013 - Continue testing with the pin combinations that appears in Table 1.
Note: Refer to Illustration 2 for 311-8401 Transmission Harness As.
Show/hide tableTable 1 PCP to Gear Harness Connections
226-0371, and 311-8401PCP Connection Gear Connection 226-0371 311-8401 Color 02 03 00 Brk Out 1 +V FWD 1 1 2 RD 2 Not Used 1 N/C 3 Not Used 6 N/C 4 +V REV 4 2 3 OR 5 -V REV 5 3 10 GN 6 Neutral Return 6 4 4 WH 7 Neutral Return 2 5 9 BU 8 -V FWD 3 6 11 BK
Expected Result:
Each pin combination in Table 1 is less than 10 ohms. All of the other pin combinations are greater than 20000 ohms.
Results:
- OK - The resistance measurements for the pin combinations are correct. Proceed to Test Step 3.
- NOT OK - The resistance measurements for the pin combinations are not correct.
Repair: Replace the harness or repair the harness.
Recheck the resistance through the PCP transmission cable.
STOP
- OK Results for the 311-8401 Gear Connector - The resistance measurement from pin 1 on the breakout to Gear pin 8 is less than 10 ohms. The resistance measurement from pin 2 on the breakout to Gear pin 5 is less than 10 ohms. All of the other pin combinations are greater than 20000 ohms. Proceed to Test Step 3.
- NOT OK Results for the 311-8401 Gear Connector - The resistance measurement from pin 1 on the breakout to Gear pin 8 is greater than 10 ohms. The resistance measurement from pin 2 on the breakout to Gear pin 5 is greater than 10 ohms. All of the other pin combinations are less than 20000 ohms.
Repair: The harness has a short circuit. Repair the harness or replace the harness.
STOP
Test Step 3. MEASURE THE RESISTANCE THROUGH THE PCP TRANSMISSION CABLE. (OPEN CIRCUIT TEST)
- Turn the keyswitch OFF.
- Disconnect the transmission cable (4) from the PCP (1).
- Disconnect the cable for the transmission solenoids (6) from the PCP transmission cable (4).
Refer to Illustration 1.
- Insert a jumper between pin 1 (+V FWD) and pin 8 (-V FWD) on the 8-pin connector that is located on the transmission.
- Measure the resistance between pin 1 (+V FWD) and pin 8 (-V FWD) on the 8-pin connector (3) located on the PCP end of the cable. Wiggle the harness during the measurement in order to reveal an intermittent condition.
- Remove the jumper from pin 1 (+V FWD) and pin 2 (-V FWD). Insert the jumper between pin 3 (-V CMD) and pin 4 (+V CMD) on the 8-pin connector (3).
- Measure the resistance between pin 6 (Neutral return) and pin 7 (Neutral signal) on the 8-pin connector (3). Wiggle the harness during a measurement in order to reveal an intermittent condition.
- Remove the jumper from pin 6 (Neutral Return) and pin 7 (Neutral signal). Insert the jumper between pin 5 (-V REV) and pin 4 (+V REV) on the 8-pin connector (3).
- Measure the resistance between pin 5 (-V REV) and pin 4 (+V REV) on the 8-pin connector (3). Wiggle the harness during the measurement in order to reveal an intermittent condition.
Expected Result:
The resistance is less than 20 Ohms for all of the readings.
Results:
- OK - The resistance is less than 20 Ohms for all of the readings. Go to Test Step 4.
- NOT OK - The resistance IS NOT less than 20 Ohms for all of the readings.
Repair: Repair the cable or replace the cable.
Recheck the resistance through the PCP transmission cable in order to ensure that the resistance is less than 20 Ohms.
STOP
Test Step 4. MEASURE THE RESISTANCE THROUGH THE TRANSMISSION SOLENOID CABLE.
- Turn the keyswitch OFF.
- Disconnect the transmission cable (6) from the PCP transmission cable (4).
Refer to Illustration 1.
- Disconnect the shift solenoids from the cable for the transmission solenoids.
- Measure the resistance of the suspect solenoid terminals. Refer to table 2.
Show/hide table
Table 2 226-0371 Transmission Connector Pinout 311-8401 Transmission Connector Pinout Measure to Signal Description 1 2 +V FWD Provides the drive to the forward solenoid. The signal is a continuous 1.5 A in order to drive the solenoid. 8 11 -V FWD 2 1, 6 Not Used 3 7, 12 4 3 +V REV Provides the drive to the reverse solenoid. The signal is a continuous 1.5 A in order to drive the solenoid. 5 10 -V REV 7 9 Neutral signal When the transmission is in NEUTRAL the signal to the PCP will be equal to 0 VDC. 6 4 Neutral return Connector pinout 6 is the neutral return.
Expected Result:
The resistance is less than 10 Ohms.
Results:
- OK - The resistance is less than 10 Ohms.
Repair: Temporarily replace the solenoid.
Recheck the resistance through the transmission solenoid cable in order to ensure that the resistance is less than 10 Ohms.
STOP
- NOT OK - The resistance is greater than 10 Ohms.
Repair: Replace the solenoid cable.
Recheck the resistance through the transmission solenoid cable in order to ensure that the resistance is less than 10 Ohms.
STOP