Circuit Description
The PRIMARY BRAKE indicator illuminates when ground is applied to the primary brake indicator control circuit.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Brake Warning System Schematics | ||||
1 | Did you review the Brake Warning System Description and Operation and perform the necessary inspections? | -- | Go to Step 2 | |
2 | Verify a fault is present. Does the system operate normally? | -- | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 |
Does the air pressure gage indicate the air pressure is above the specified value? | 480 kPa (70 psi) | Go to Step 4 | |
4 |
Does the PRIMARY BRAKE indicator turn OFF? | -- | Go to Step 7 | Go to Step 5 |
5 |
Does the PRIMARY BRAKE indicator turn OFF? | -- | Go to Step 6 | Go to Step 8 |
6 | Replace the multifunction alarm module. Refer to Multifunction Alarm Module Replacement in Instrument Panel, Gages, and Console. Did you complete the replacement? | -- | Go to Step 10 | -- |
7 | Replace the low air pressure switch. Refer to Low Air Pressure Switch Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- |
8 | Inspect the primary brake indicator control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9 |
9 | Replace the instrument panel cluster. Did you complete the replacement? | -- | Go to Step 10 | -- |
10 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
