B2122

B2122-IGNITION RUN CONTROL 1 CIRCUIT LOW







Theory of Operation

The family of B2100 DTCs typically describes ignition performance related faults. These are often caused by a contradiction of switch status information. For example, if an ECU receives a bussed message indicating ignition switch position but the state of a hardwired ignition circuit indicates another switch position a B2100 series DTC would likely result.

These DTCs can be caused by a number of conditions including:

- loose connections
- missing or blown fuses
- faulty component
- vehicle no start or long crank time

Verify the proper operation of the starting system and verify that this DTC is active before proceeding with the diagnostic test.

- When Monitored:
With the ignition on.

- Set Condition:
The Totally Integrated Power Module (TIPM) will set this code when a short to ground condition is detected on the Ignition Run Control 1 circuit.





1. CHECK FOR ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)

NOTE: Check all related fuses before proceeding with diagnostic procedure.

1. Turn the ignition on.
2. Using the scan tool, read the active DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- If the DTC is stored, check for an intermittent condition. Using the wiring diagram/schematic as a guide, visually inspect the related wiring harness connectors. Look for broken, bent, pushed out or corroded terminals.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. OCCUPANT RESTRAINT CONTROLLER (ORC)

WARNING: To avoid possible serious or fatal injury, turn the ignition off, disconnect the battery and wait two minutes before proceeding.

1. Disconnect the ORC C2 harness connector.
2. Turn the ignition on.
3. Reconnect the battery.
4. Using the scan tool, read DTCs.

Does the scan tool display active DTC B2122-IGNITION RUN CONTROL 1 CIRCUIT LOW?

Yes

- Go To 3

No

- Replace the ORC.
- Perform the ORC VERIFICATION TEST. Occupant Restraint Controller (ORC) Verification Test.

3. A/C HEATER CONTROL
1. Turn the ignition off.
2. Disconnect the A/C Heater Control C1 harness connector.
3. Turn the ignition on.
4. Using the scan tool, read DTCs.

Does the scan tool display active DTC B2122-IGNITION RUN CONTROL 1 CIRCUIT LOW?

Yes

- Go To 4

No

- Replace the A/C Heater Control.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. (F100) FUSED IGNITION SWITCH OUTPUT (RUN) SHORTED TO GROUND




1. Turn the ignition off.
2. Disconnect the TIPM C8 harness connector.
3. Measure the resistance between ground and the (F100) Fused Ignition Switch Output (Run) circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the short to ground in the (F100) Fused Ignition Switch Output (Run) circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. (F921) FUSED IGNITION SWITCH OUTPUT (RUN) SHORTED TO GROUND




1. Disconnect the TIPM C3 harness connector.
2. Measure the resistance between ground and the (F921) Fused Ignition Switch Output (Run) circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the short to ground in the (F921) Fused Ignition Switch Output (Run) circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the TIPM.
- Perform the BODY VERIFICATION TEST. Body Verification Test.