Low Beam and High 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 the 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 headlamps light? | -- | System OK | Go to Step 2 |
2 | Probe the RED (2) wire at the headlamp switch connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 3 |
3 | Locate and repair the open circuit in the RED (2) wire between the battery junction block and the headlamp switch. Is the repair complete? | -- | Go to Step 1 | -- |
4 | Probe the YEL (10) wire at the headlamp switch connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 5 |
5 | Replace the headlamp switch. Is the repair complete? | -- | Go to Step 1 | -- |
6 | Probe the TAN (12) wire at the forward lamp interface connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 10 | Go to Step 7 |
7 | Probe the YEL (10) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 9 |
8 | Replace the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
9 | Locate and repair the open circuit between the headlamp switch and the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
10 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
Low Beam and High 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 headlamps light? | -- | System OK | Go to Step 2 |
2 | Probe the hot lead wire at the headlamp switch connector with a test lamp Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 3 |
3 | Locate and repair the open circuit in the hot lead between the battery junction block and the headlamp switch. Is the repair complete? | -- | Go to Step 1 | -- |
4 | Probe the WHT (67) wire at the headlamp switch connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 6 | Go to Step 5 |
5 | Replace the headlamp switch. Is the repair complete? | -- | Go to Step 1 | -- |
6 | Probe the WHT (69) wire at the forward lamp interface connector with a test lamp. Does the test lamp illuminate? | -- | Go to Step 10 | Go to Step 7 |
7 | Probe the WHT (67) wire at the headlamp dimmer switch with a test lamp. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 9 |
8 | Replace the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
9 | Locate and repair the open circuit between the headlamp switch and the headlamp dimmer switch. Is the repair complete? | -- | Go to Step 1 | -- |
10 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
