NAG1 Automatic Transmission - Shifter Diagnostics: Other Dodge Nitro I

Monitor Conditions

1. When Monitored: Continuously with the ignition in the run position.

Set Conditions

1. Set Condition: When monitored battery voltage drops below 6.0 volts.

Possible Causes

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

Scheme 336

Scheme 337

1. CHECK FOR ENGINE CHARGING SYSTEM DTCS With the scan tool, read Engine DTCs. Are there any Engine Charging System DTCs present? Yes Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article and perform the appropriate symptom. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 2 .
2. CHECK (F1) IGNITION UNLOCK RUN START CIRCUIT Turn the ignition off to the lock position. Disconnect the Shift Lever Assembly harness connector. Turn the ignition on. Using a 12-volt test light connected to ground, check the (F1) Ignition Unlock Run Start circuit in the Shift Lever Assembly harness connector. NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? Yes Go To 3 . No Repair the (F1) Ignition Unlock Run Start circuit for high resistance. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) .
3. CHECK (Z910) GROUND CIRCUITS Turn the ignition off to the lock position. Using a 12-volt test light connected to 12-volts, check the (Z910) Ground circuit in the Shift Lever Assembly harness connector. NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? Yes Go To 4 . Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Repair the (Z910) Ground circuit for high resistance.
4. SHIFT LEVER ASSEMBLY Reconnect all disconnected harness connectors. With the scan tool, erase Shift Lever DTC's. Start the engine and raise the engine speed to 2000 rpm. With the scan tool, read Shift Lever DTC's. Did the DTC P0562-BATTERY VOLTAGE LOW DTC reset? Yes Replace the Shift Lever Assembly per the Service Information Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Test Complete.

1. When Monitored: Continuously with the ignition in the run position.

1. Set Condition: When the monitored battery voltage rises above 16.0 volts.

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The Shift Lever Assembly monitors ignition voltage. The DTC will set, if the monitored battery voltage rises above 16.0 volts.

1. When Monitored: Continuously with the ignition in the run position.

1. Set Condition: If the Shift Lever Assembly controller detects an invalid calibration (checksum value).

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The Shift Lever Assembly (SLA) Electronic Shift Module (ESM) performs various internal tests to verify proper controller operation. This DTC indicates that there is an issue with the Shifter's internal processor.

1. When Monitored: Continuously with the ignition in the run position.

1. Set Condition: The DTC will set if the high side driver detects a short to ground for 10 seconds.

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The brake switch signal must be active before the shift lever can be moved out of the park position. The Shift Lever Assembly (SLA) Electronic Shift Module (ESM) receives two brake switch signals. The first signal is a CAN C Bus message sent to the shift lever assembly. The second signal is a hard wired brake switch signal to the shift lever assembly. The CAN C Bus message is the primary brake switch signal and the hard wired signal serves as the backup brake switch signal.

Scheme 338

1. ENGINE DTCS PRESENT With the scan tool, read Engine DTCs. Are there any Engine brake DTCs present? Yes Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article and perform the appropriate diagnostic procedure. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 2 .
2. ABS MODULE DTCS PRESENT With the scan tool, read ABS Module DTCs. Are there any ABS DTCs present? Yes Refer to «ABS - ELECTRICAL DIAGNOSTICS»(ref-306150) and perform the appropriate diagnostic procedure. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 3 .
3. (L51) BRAKE SWITCH SIGNAL SHORT TO GROUND Turn the ignition off to the lock position. Disconnect the Shift Lever Assembly harness connector. NOTE: Check connectors - Clean/repair as necessary. Measure the resistance between ground and the (L51) Brake Switch Signal circuit. Is the resistance below 5.0 ohms? Yes Repair the (L51) Brake Switch Signal for a short to ground. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Using the schematics as a guide, inspect the wiring and connectors. Repair as necessary. Pay particular attention to all power and ground circuits. If no problems are found, replace the Shift Lever Assembly per the Service Information. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) .

1. When Monitored: Continuously with the ignition in the run position.

1. Set Condition: The DTC will set if the high side driver detects an open load for 10 seconds.

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The brake switch signal must be active before the shift lever can be moved out of the park position. The Shift Lever Assembly (SLA) Electronic Shift Module (ESM) receives two brake switch signals. The first signal is a CAN C Bus message sent to the shifter lever assembly. The second signal is a hard wired brake switch signal to the shifter lever assembly. The CAN C Bus message is the primary brake switch signal and the hard wired signal serves as the backup brake switch signal. These two brake switch signals are compared against each other to verify proper brake switch operation.

Scheme 339

Scheme 340

1. ENGINE DTCs PRESENT With the scan tool, read Engine DTCs. Are there any Engine brake DTCs present? Yes Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article and perform the appropriate diagnostic procedure. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 2 .
2. ABS MODULE DTCs PRESENT With the scan tool, read ABS Module DTCs. Are there any ABS DTCs present? Yes Refer to «ABS - ELECTRICAL DIAGNOSTICS»(ref-306150) and perform the appropriate diagnostic procedure. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 3 .
3. (L51) BRAKE SWITCH SIGNAL OPEN Turn the ignition off to the lock position. Disconnect the Shift Lever Assembly harness connector. Disconnect the Stop Lamp Switch harness connector. NOTE: Check connectors - Clean/repair as necessary. Measure the resistance of the (L51) Brake Switch Signal circuit between the Shift Lever Assembly harness connector and the Stop Lamp Switch. Is the resistance above 5.0 ohms? Yes Repair the (L51) Brake Switch Signal for an open. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Go To 4 .
4. (L51) BRAKE SWITCH SIGNAL SHORT TO VOLTAGE Turn the ignition off to the lock position. Disconnect the Shift Lever Assembly harness connector. NOTE: Check connectors - Clean/repair as necessary. Turn the ignition on. Measure the voltage of the (L51) Brake Switch Signal circuit. Is the voltage above 0.5 volts? Yes Repair the (L51) Brake Switch Signal for a short to voltage. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) . No Replace the Shift Lever Assembly per the Service Information. Perform «NAG1 TRANSMISSION VERIFICATION TEST»(ref-306222-S20864619532008120900000) .

1. When Monitored: Continuously with the ignition in the run position.

1. Set Condition: When the expected switch state is not correctly sensed by the Shift Lever Assembly. If the upshift switch signal is detected as active in gear position other than drive.

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The AutoStick Switch is integrated into the Shift Lever Assembly. The gear requested by the AutoStick selection is then sent over the CAN C bus to the TCM to engage the requested gear.

1. When Monitored: Continuously with the ignition in the run position and with the shift lever in AutoStick mode.

1. Set Condition: When the expected switch state is not correctly sensed by the Shift Lever Assembly (SLA) Electronic Shift Module (ESM). If the upshift switch signal is detected as active in gear position other than drive or both upshift and downshift signals are active at the same time.

Always perform the NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.

The AutoStick Switch is integrated into the Shift Lever Assembly. The gear requested by the AutoStick selection is then sent over the CAN C bus from the Electronic Shift Module (ESM) to the TCM to engage the requested gear.