Low Beam Headlamps Inoperative P72
Circuit Description
Voltage is supplied to the headlight dimmer switch at all times. The headlight switch includes a self-resetting circuit breaker. The circuit breaker opens when the headlight circuit draws too much current. When the circuit breaker opens, current flow is interrupted. With no current flow, the circuit breaker cools and resets automatically. When the headlight switch is in HEAD, the headlight dimmer switch directs voltage to LOW BEAM or HIGH BEAM. The HIGH BEAM indicator also receives voltage along with the high beams.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the low beam headlamps come on? | -- | System OK | Go to Step 2 |
2 | Probe the TAN (12) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 3 |
3 | Probe the TAN (12) wire at the headlamp dimmer switch connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 5 |
4 | Locate and repair the open circuit in the TAN (12) wire between the dimmer switch connector and C205. Is the repair complete? | -- | Go to Step 1 | -- |
5 | Probe the YEL (10) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 7 |
6 | Replace the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
7 | Locate and repair the open circuit in the YEL (10) wire between the headlamp switch connector and the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
8 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
Low Beam Headlamps Inoperative P92
Circuit Description
Voltage is supplied to the headlight dimmer switch at all times. The headlight switch includes a self-resetting circuit breaker. The circuit breaker opens when the headlight circuit draws too much current. When the circuit breaker opens, current flow is interrupted. With no current flow, the circuit breaker cools and resets automatically. When the headlight switch is in HEAD, the headlight dimmer switch directs voltage to LOW BEAM or HIGH BEAM. The HIGH BEAM indicator also receives voltage along with the high beams.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the low beam headlamps come on? | -- | System OK | Go to Step 2 |
2 | Probe the WHT (69) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 3 |
3 | Probe the WHT (69) wire at the headlamp dimmer switch connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 5 |
4 | Locate and repair the open circuit in the WHT (69) wire between the dimmer switch connector and C205. Is the repair complete? | -- | Go to Step 1 | -- |
5 | Probe the WHT (67) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 7 |
6 | Replace the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
7 | Locate and repair the open circuit in the WHT (67) wire between the headlamp switch connector and the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
8 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
