The body control module (BCM) supplies battery positive voltage to the center high mounted stop lamp (CHMSL), powertrain control module (PCM), engine temperature control (ETC), and antilock brake system (ABS) module through the stop lamp supply voltage circuits when the brakes are applied.
This diagnostic procedure supports the following DTC:
DTC B3445 Stop Lamp Circuit
The battery voltage must be between 9-16 volts.
DTC B3445 will set when the BCM detect an open or short to ground in the stop lamp supply voltage circuits.
The CHMSL will not operate.
• | This DTC will clear on current status after the condition for setting the fault is corrected. |
• | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
• | History and current DTCs can be cleared using a scan tool. |
Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Master Electrical Component List | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Does the center high mounted stop lamp (CHMSL) illuminate? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 |
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 5 |
4 | Test for a short to ground in the stop lamp voltage supply circuits. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 6 |
5 | Test for a poor connection or an open in the stop lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 6 |
6 | Replace the body control module (BCM). Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |