Circuit Description
The TCC normally closed brake switch supplies a B+ signal to the PCM. The circuit is opened when the brakes are applied. The stop lamp/cruise control normally open brake switch supplies a B+ signal to the PCM when the brake is applied.
Conditions for Running the DTC
Vehicle mph greater than 0.
Conditions for Setting the DTC
| • | The switches disagree for 10 consecutive minutes. |
| • | The TCC and the cruise control brake switches are not toggling open and closed during six brake applications on the same ignition cycle. |
Action Taken When the DTC Sets
| • | The PCM will not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | A History DTC will clear after forty consecutive engine warm up cycles, if this or any other emmision related diagnosic does not report any failures. |
| • | Use of a scan tool will clear the DTC codes. |
Diagnostic Aids
Refer to PCM Intermittent Diagnostic Trouble Codes or Performance. Check the driving habits of the customer and/or unusual traffic conditions (i.e. stop and go, expressway traffic).
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Important: Before clearing any DTCs, use the scan tool Capture Info to save the Freeze Frame and Failure records for reference. The control module's data is deleted once the Clear Info function is used. Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 |
Does the scan tool display the cruise brake switch Closed and then Open when the brake is applied? | -- | ||
3 | Apply the brakes again. Does the scan tool display the brake switch Open and then Closed when the brake is applied? | -- | ||
Is the test lamp ON? | -- | |||
5 |
Is the test lamp ON? | -- | ||
Does the scan tool display the brake switch Closed? | -- | |||
7 |
Is the test lamp ON? | -- | ||
8 |
Does the scan tool display the Cruise Brake switch Closed? | -- | ||
9 | The DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored refer to the applicable DTC table(s) first. Are any additional DTCs stored? | -- | Go to the applicable DTC table | Go to Diagnostic Aids |
10 | Check the normally open feed circuit (terminal B) for an open or short to ground. Repair as necessary. Refer to Wiring Repairs . Is the action complete? | -- | -- | |
11 |
Is the action complete? | -- | ||
12 | Check the normally open brake switch signal circuit for and open or short to ground. Repair as necessary, refer to Wiring Repairs . Did you perform a repair? | -- | ||
13 | Check the normally open brake switch signal circuit for a proper connection at PCM. Repair as necessary, refer to Wiring Repairs . Did you perform a repair? | -- | ||
14 | Check the normally closed feed circuit (terminal F) for an open or short to ground. Repair as necessary, refer to Wiring Repairs . Is the action complete? | -- | -- | |
15 | Check the normally closed cruise brake switch signal circuit for an open or short to ground. Repair as necessary, refer to Wiring Repairs . Did you perform a repair? | -- | ||
16 | Check the normally closed cruise brake switch signal circuit for a proper connection at PCM. Repair as necessary, refer to Wiring Repairs . Did you perform a repair? | -- | ||
17 | Replace the stoplamp switch. Is the action complete? | -- | -- | |
18 |
Important: The new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Is the action complete? | -- | -- | |
19 |
Does the scan tool indicate the diagnostic passed? | -- | ||
20 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK |
