B18BB

B18BB-WINDOW CONTROL CIRCUIT LOW - TIPM






NOTE: The schematic shows just the Left Rear Window Motor circuit. The other Passenger Window Motor circuits are similar.

For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
Whenever the module is awake.

- Set Condition:
When the Totally Integrated Power Module (TIPM) senses a draw of between 65 and 100 amps for 80 ms., this code will set.

NOTE: The most probable cause for this DTC to set is that the driver held all four window switches down or up for an extended period of time thereby causing the high side driver, in the TIPM, to overheat and cut out. Once the high side driver is opened, it will remain open for approximately 10 seconds or until the next key cycle. However, the code will remain as stored.





Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.
With the scan tool, record and erase DTC's
Cycle the ignition switch off for 30 seconds then on.
Ensure the Window Lock Out Switch is ON.
Operate the Driver Window Switch in all positions several times.
Operate each Passenger Window Switch in both directions several times.
Wait 30 seconds.
With the scan tool, read DTC's.
Does the scan tool display B18BB-WINDOW CONTROL CIRCUIT LOW?

Yes

- Go To 2

No

- The conditions that caused this code to set are not present at this time. Check for a sticking switch or any window motor that is not operating properly and using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

2. (F981) IGNITION SWITCH OUTPUT CIRCUIT SHORT TO GROUND




Turn the ignition off.
Disconnect the Driver Power Window Switch C1 and C2 connectors.
Check the Master Switch for an internal short. Replace if necessary.
Turn the ignition on.
Measure the voltage between ground and the (F981) Ignition Switch Output circuit in the Driver Power Window Switch C2 connector
Is the voltage above 11.5 volts?

Yes

- Go To 3

No

- Go To 7

3. WINDOW DRIVER CIRCUITS SHORT TO GROUND




Turn the ignition off.
Measure the resistance between ground and each Window Driver (Up and Down) circuit in the Driver Window Switch C1 connector.
Is the resistance below 10,000.0 ohms in any Window Driver circuit in the C1 connector?

No

- Go To 4

Yes

- Locate and repair the Window Driver circuit for a short to ground. The short circuit could be in either Window Driver wire or the affected motor.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

4. FRONT WINDOW DRIVER CIRCUIT SHORT TO GROUND




Measure the resistance between ground and the Front Window Driver (Up and Down) circuits in the Driver Window Switch C2 connector.
Is the resistance below 10,000.0 ohms in either or both circuits?

Yes

- Repair the Window Driver circuit for a short to ground. The short circuit could be in either Window Driver wire or the motor.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 5

5. (Q15) WINDOW LOCK OUT SWITCH OUTPUT CIRCUIT SHORT TO GROUND




Measure the resistance between ground and the (Q15) Window Lock Out Switch Output circuit
Is the resistance below 10,000.0 ohms?

No

- Go To 6

Yes

- Repair the (Q15) Window Lock Out Switch Output circuit for a short to ground. The short could be in any wire going to a Passenger Window Switch or in one of the Passenger Window Switches
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

6. CHECK EACH WINDOW DRIVER UP CIRCUIT FOR A SHORT TO THE WINDOW DRIVER DOWN CIRCUIT




Measure the resistance of each window motor circuit between the Window Up circuit and the Window Down circuit in the Master Window Switch C1 and C2 connectors. Do this test for all four motors.
Is the resistance below 0.5 ohms in any of the Window Motor circuits?

Yes

- Disconnect the Window Motor and retest the circuits. If the resistance between the circuits is above 20,000.0 ohms, replace the motor . If the resistance is still low, check the Passenger Window Switch. If the switch is not shorted, repair the Window Driver or Master Window Switch circuits for a short to each other.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Test complete.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

7. (F981) IGNITION SWITCH OUTPUT CIRCUIT SHORT TO GROUND




Turn the ignition off.
Disconnect the TIPM C7 connector.
Measure the resistance between ground and the (F981) Ignition Switch Output circuit in the TIPM C7 connector.
Is the resistance below 10,000.0 ohms?

Yes

- Repair the (F981) Ignition Switch Output circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test

No

- Go To 8

8. (F981) IGNITION SWITCH OUTPUT CIRCUIT OPEN




Measure the resistance of the (F981) Ignition Switch Output circuit between the TIPM C7 connector and the Driver Power Window Switch C2 connector.
Is the resistance below 5.0 ohms?

Yes

- Repair the (F981) Ignition Switch Output circuit for an open
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test

No

- Replace the Totally Integrated Power Module
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test