Turn Lamps Inoperative P72
Circuit Description
With the ignition in RUN or START, voltage is supplied through the TURN-B/U fuse and the turn flasher to the normally open contact of the hazard flasher switch in the turn signal/hazard switch.
With the turn switch in "LH TURN," voltage is supplied to both the LH turn indicator and the LH front park and turn light LT BLU (14) wires. Voltage is supplied to the LH tail, brake and turn signal light YEL (18) wires.
The lights go on immediately. The lights begin to flash when the current flow heats up the timing element in the flasher. The timing element repeatedly opens and closes the circuit.
The voltage supplied to the LH park and turn signal light will also be supplied to the LH sidemarker light. If the headlight switch is in the OFF position, the LH sidemarker light will find a path through splice S123 and the park and turn signal light to ground. The sidemarker light provides low resistance paths to ground. The sidemarker lights will flash with the turn signal lights.
When the headlight switch is in "HEAD" or "PARK," voltage is supplied through the TAIL LPS fuse, the headlight switch, and S122 to the sidemarker and park lights. If the turn signal/hazard switch is in "TURN LEFT," the LH sidemarker light will have voltage at both connections and will go out. When the flasher moves voltage to the turn signal light, the sidemarker light will be grounded through the turn signal light and will go on. In this way, the LH sidemarker light will flash on when the LH park and turn signal light goes off, and off when the turn signal light goes on.
With the turn signal/hazard switch in "TURN RIGHT," voltage will be supplied to the RH lights in the same manner as described previously.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the turn signal lamps flash? | -- | System OK | Go to Step 2 |
2 | Probe the PPL (16) wire at C279 with a test lamp. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 3 |
3 | Probe the DK BLU (38) wire at the turn signal flasher socket with a test lamp. Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 6 |
4 |
Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 5 |
5 | Replace the turn/hazard switch. Is the repair complete? | -- | Go to Step 1 | -- |
6 | Locate and repair the open circuit in the DK BLU (38) wire between the turn signal flasher socket and the fuse block. Is the repair complete? | -- | Go to Step 1 | -- |
7 | Replace the turn signal flasher unit. Is the repair complete? | -- | Go to Step 1 | -- |
8 |
Has C279 been examined and the faults corrected? | -- | Go to Step 1 | -- |
Turn Lamps Inoperative P92
Circuit Description
With the ignition in RUN or START, voltage is supplied from a circuit breaker through a turn flasher to the normally open contact in the turn signal/hazard switch.
With the turn switch in "LH TURN," voltage is supplied to both the LH turn indicator and the LH front park and turn light LT BLU (14) wires. Voltage is supplied to the LH tail, brake and turn signal light YEL (18) wires.
The lamps go on immediately. The lamps begin to flash when the current flow heats up the timing element in the flasher. The timing element repeatedly opens and closes the circuit.
The voltage supplied to the LH park and turn signal light will also be supplied to the LH sidemarker light. If the headlight switch is in the OFF position, the LH sidemarker light will find a path through splice S123 and the park and turn signal light to ground. The sidemarker light provides low resistance paths to ground. The sidemarker lamps will flash with the turn signal lamps.
When the headlight switch is in "HEAD" or "PARK," voltage is supplied through the TAIL LPS fuse, the headlight switch, and S122 to the sidemarker and park lamps. If the turn signal/hazard switch is in "TURN LEFT," the LH sidemarker light will have voltage at both connections and will go out. When the flasher moves voltage to the turn signal light, the sidemarker light will be grounded through the turn signal light and will go on. In this way, the LH sidemarker light will flash on when the LH park and turn signal light goes off, and off when the turn signal light goes on.
With the turn signal/hazard switch in "TURN RIGHT," voltage will be supplied to the RH lamps in the same manner as described previously.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the turn signal lamps flash? | -- | System OK | Go to Step 2 |
2 | Probe the WHT (71) wire at C205 with a test lamp. Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 3 |
3 | Probe the WHT (71) wire at the turn signal flasher socket with a test lamp. Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 6 |
4 |
Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 5 |
5 | Replace the turn/hazard switch. Is the repair complete? | -- | Go to Step 1 | -- |
6 | Locate and repair the open circuit in the WHT (71) wire between the turn signal flasher socket and the fuse block. Is the repair complete? | -- | Go to Step 1 | -- |
7 | Replace the turn signal flasher unit. Is the repair complete? | -- | Go to Step 1 | -- |
8 |
Has C205 been examined and the faults corrected? | -- | Go to Step 1 | -- |
Turn Lamps Inoperative P72 One Side Only
Circuit Description
With the ignition in RUN or START, voltage is supplied through the TURN-B/U fuse and the turn flasher to the normally open contact of the hazard flasher switch in the turn signal/hazard switch.
With the turn switch in "LH TURN," voltage is supplied to both the LH turn indicator and the LH front park and turn light LT BLU (14) wires. Voltage is supplied to the LH tail, brake and turn signal light YEL (18) wires.
The lights go on immediately. The lights begin to flash when the current flow heats up the timing element in the flasher. The timing element repeatedly opens and closes the circuit.
The voltage supplied to the LH park and turn signal light will also be supplied to the LH sidemarker light. If the headlight switch is in the OFF position, the LH sidemarker light will find a path through splice S123 and the park and turn signal light to ground. The sidemarker light provides low resistance paths to ground. The sidemarker lights will flash with the turn signal lights.
When the headlight switch is in "HEAD" or "PARK," voltage is supplied through the TAIL LPS fuse, the headlight switch, and S122 to the sidemarker and park lights. If the turn signal/hazard switch is in "TURN LEFT," the LH sidemarker light will have voltage at both connections and will go out. When the flasher moves voltage to the turn signal light, the sidemarker light will be grounded through the turn signal light and will go on. In this way, the LH sidemarker light will flash on when the LH park and turn signal light goes off, and off when the turn signal light goes on.
With the turn signal/hazard switch in "TURN RIGHT," voltage will be supplied to the RH lights in the same manner as described previously.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the turn signals work on both sides of the coach? | -- | System OK | Go to Step 2 |
2 |
Do the lamps flash on the side where the turn signals don't? | -- | Go to Step 3 | Go to Step 4 |
3 |
Does the test lamp flash? | -- | Go to Step 7 | Go to Step 5 |
4 | Probe the LT BLU (14) or DK BLU (15) wire at C205. Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 6 |
5 | Replace the turn signal flasher unit. Is the repair complete? | -- | Go to Step 1 | -- |
6 | Locate and repair the open circuit in the LT BLU (14) or DK BLU (15) wire with a test lamp. Does the test lamp illuminate? | -- | Go to Step 1 | -- |
7 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
Turn Lamps Inoperative P92 One Side Only
Circuit Description
With the ignition in RUN or START, voltage is supplied from a circuit breaker through a turn flasher to the normally open contact in the turn signal/hazard switch.
With the turn switch in "LH TURN," voltage is supplied to both the LH turn indicator and the LH front park and turn light LT BLU (14) wires. Voltage is supplied to the LH tail, brake and turn signal light YEL (18) wires.
The lamps go on immediately. The lamps begin to flash when the current flow heats up the timing element in the flasher. The timing element repeatedly opens and closes the circuit.
The voltage supplied to the LH park and turn signal light will also be supplied to the LH sidemarker light. If the headlight switch is in the OFF position, the LH sidemarker light will find a path through splice S123 and the park and turn signal light to ground. The sidemarker light provides low resistance paths to ground. The sidemarker lamps will flash with the turn signal lamps.
When the headlight switch is in "HEAD" or "PARK," voltage is supplied through the TAIL LPS fuse, the headlight switch, and S122 to the sidemarker and park lamps. If the turn signal/hazard switch is in "TURN LEFT," the LH sidemarker light will have voltage at both connections and will go out. When the flasher moves voltage to the turn signal light, the sidemarker light will be grounded through the turn signal light and will go on. In this way, the LH sidemarker light will flash on when the LH park and turn signal light goes off, and off when the turn signal light goes on.
With the turn signal/hazard switch in "TURN RIGHT," voltage will be supplied to the RH lamps in the same manner as described previously.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Do the turn signals work on both sides of the coach? | -- | System OK | Go to Step 2 |
2 |
Do the lamps flash on the side where the turn signals don't? | -- | Go to Step 3 | Go to Step 4 |
3 |
Does the test lamp flash? | -- | Go to Step 7 | Go to Step 5 |
4 | Probe the WHT (13) or DK BLU (12) wire at C205. Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 6 |
5 | Replace the turn signal flasher unit. is the repair complete? | -- | Go to Step 1 | -- |
6 | Locate and repair the open circuit in the WHT (13) or DK BLU (12) wire with a test lamp. Does the test lamp illuminate? | -- | Go to Step 1 | -- |
7 | Refer to the coach manufacturer's repair manual in order to diagnose and repair the system. Is the repair complete? | -- | System OK | -- |
