P1607

P1607-PCM INTERNAL SHUTDOWN TIMER SLOW RATIONALITY

For a complete wiring diagram Refer to the Wiring Information.

- When Monitored:
Continuously.

- Set Condition:
Upon power up, the PCM compares the change in engine coolant temp sensor since last engine shut down and compares it to the amount of time the engine was turned off. If not enough time has occurred to account for the difference in engine coolant temperature then the fault will set. Two Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure

1. PENDING TEMPERATURE SENSOR DTCS
1. Turn the ignition on.
2. Start the engine and allow it to reach operating temperature.
3. With the scan tool, select View DTCs.

Are there any pending Engine Coolant Temperature sensor, Ambient Air Temperature sensor, or general temperature DTCs?

Yes

- Diagnose and repair any temperature sensor DTCs and retest.
- Perform the PCM Verification Test. PCM Verification Test

No

- Go to 2

2. DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, select View DTCs and review the DTC environmental information for this DTC.

Is the good trip counter greater than 0?

Yes

- The DTC is not active at this time. Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking for an Intermittent DTC

No

- Go to 3

3. STUCK ENGINE OFF TIMER
1. Using the scan tool under the PCM Data menu, read and record the IGNITION OFF TIME.
2. Start and allow the engine to idle.
3. Turn key off and remove from ignition switch for exactly 3 minutes and 15 seconds.
4. Turn key on but leave engine off.
5. Using the scan tool read the IGNITION OFF TIME.

Does the most recent IGNITION OFF TIME equal 3 minutes?

Yes

- Go to 5

No

- Go to 4

4. IGNITION OFF TIME
1. Compare the IGNITION OFF TIME written down with the IGNITION OFF TIME after the 3 minute 15 second shutdown.

Did it change?

Yes

- Go to 5

No

- Go to 7

5. LOW BATTERY VOLTAGE AT PCM

NOTE: A loss of battery voltage to the module while the module is powered down is the most likely cause of this DTC.

1. Inspect all PCM power and ground circuits.
2. Inspect and test the battery.
3. Inspect the generator drive belt for proper alignment and adjustment.
4. Inspect the vehicle for aftermarket accessories that may exceed the generator system output.
5. Inspect the fuses in the IPM. If an open fuse is found, use the wire diagram/schematics as a guide and inspect the wiring and connectors for a damaged or shorted circuit.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. PCM Verification Test

No

- Go to 6

6. FUSED B+ CIRCUIT OPEN OR HIGH RESISTANCE
1. With a 12-volt test light connected to ground, check the Fused B+ circuit at the C1 PCM harness connector.
2. Check the circuit with the ignition switch in the OFF, ON, and START positions.

NOTE: The test light should be illuminated and bright regardless of the position of the ignition switch. Compare the brightness to that of a direct connection to the battery.

3. Wiggle test the circuits while checking with the test light to check the circuit for an intermittent problem.

Is the test light illuminated and bright in each of the ignition switch positions?

Yes

- Go to 8

No

- Repair the circuit as necessary.
- Perform the PCM Verification Test. PCM Verification Test

7. RESET STUCK TIMERTurn the ignition off.
1. Disconnect the PCM harness connectors for five minutes.
2. Reconnect the PCM harness connectors.
3. Start and allow the vehicle to Idle for 30 seconds.
4. Turn key off and remove from ignition switch for exactly 2 minutes and 15 seconds.
5. Ignition on, engine not running.
6. Using the scan tool go into PCM DATA menu, read the IGNITION OFF TIME.

Did the timer equal 2 minutes?

Yes

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test. PCM Verification Test

No

- Go to 8

8. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect Powertrain Control Module power and ground circuits.
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data and wiggle test the wiring and connectors.
5. Look for the any data to change or for the DTC to reset during the wiggle test.
6. Search for any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. PCM Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test. PCM Verification Test