Drivetrain Control Module (DTCM)

C2100-BATTERY VOLTAGE LOW





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
Continuously.

- Set Condition:
The Drive Train Control Module (DTCM) detects that system voltage is below 8.5 volts for 60 seconds with engine RPM greater than 1500.





1. CHARGING SYSTEM DTCS PRESENT
1. Ignition on, engine not running.
2. With the scan tool, read DTCs in the PCM.

Are there any Charging System or related voltage DTCs present?

Yes

- Testing and Inspection Perform the appropriate charging system or battery diagnostic procedure.

No

- Go To 2

2. VERIFY THE DTC IS ACTIVE
1. With the scan tool, read DTCs.

Is the DTC active at this time?

Yes

- Go To 3

No

- Go To 6

3. (A913) FUSED (B+) CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off to the lock position
2. Disconnect the DTCM harness connector.
3. Ignition on, engine not running.
4. With a 12-volt test light connected to ground, check the (A913) Fused (B+) circuit in the DTCM 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

No

- Repair the (A913) Fused (B+) circuit for an open circuit or high resistance.
- Perform the DTCM VERIFICATION TEST. DTCM Verification Test.

4. (F348) DRIVETRAIN CONTROL RELAY CONTROL CIRCUIT OPEN OR HIGH RESISTANCE




1. With a 12-volt test light connected to ground, check the (F348) Drivetrain Control Relay Control circuit in the DTCM 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 5

No

- Repair the (F348) Drivetrain Control Relay Control circuit for an open circuit or high resistance.
- Perform the DTCM VERIFICATION TEST. DTCM Verification Test.

5. (Z901) GROUND CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off to the lock position
2. With a 12-volt test light connected to B+, check the (Z901) Ground circuit in the DTCM 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

- Replace the Drive Train Control Module (DTCM).
- Perform the DTCM VERIFICATION TEST. DTCM Verification Test.

No

- Repair the (Z901) Ground circuit for an open circuit or high resistance.
- Perform the DTCM VERIFICATION TEST. DTCM Verification Test.

6. INTERMITTENT WIRING HARNESS AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
3. Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
4. Look for the data to change or for the DTC to reset during the wiggle test.

Were any problems found?

Yes

- Repair as necessary.
- Perform the DTCM VERIFICATION TEST. DTCM Verification Test.

No

- Test complete.