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 Refer to 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.







Theory of Operation


One of the probable causes 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. As you can see from the other possible causes, any circuit in the Power Window System that could go to ground can set this code.


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. ISOLATE THE CAUSE
Cycle the ignition switch off for 30 seconds then on.
Erase the DTC's
Turn the lock out switch off.
Try each window from the Driver Window Switch and stop if a window quits working.
Turn the window lock out switch on and try each window from the passenger switches and stop if a window quits working.
If the vehicle is equipped with the power sliding backlite, try it to see if works properly without tripping the driver in the TIPM.
Try every possible cause listed above to isolate the cause for the (F30) Ignition Switch Output circuit opening.
Did the (F30) Ignition Switch Output circuit open and set the B18BB DTC?

Yes


- If the power windows did not operate at all, disconnect the TIPM C9 connector, turn the ignition off and check for a short to ground in the (F30) circuit from the TIPM. If there is no short to ground, replace the TIPM. If the windows worked and then quit when doing the steps above, use the schematics in Diagrams/Electrical to isolate the problem.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test


No


- If the DTC set in the first step, there has to be an intermittent short to ground. Re-test the system for every possible cause.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test