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For 1990-2009 cars only

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 LOW BEAM or HIGH BEAM. The HIGH BEAM indicator also receives voltage along with the high beams.

P72 High Beam Headlamps Inoperative

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition switch ON.
  2. Turn the headlamp switch ON.
  3. Select HIGH at the dimmer switch.

Do the high beam headlamps come on?

--

System OK

Go to Step 2

2

Probe the LT GRN (11) wire at the forward lamp interface connector with a test lamp.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 3

3

Probe the LT GRN (11) 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 LT GRN (11) wire between the headlamp dimmer switch and the forward lamp interface connector.

Is the repair complete?

--

Go to Step 1

--

5

Replace the headlamp dimmer switch.

Is the repair complete?

--

Go to Step 1

--

6

Refer to the coach manufacturer's repair manual in order to diagnose and repair the system.

Is the repair complete?

--

System OK

--

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.

P92 High Beam Headlamps Inoperative

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition switch ON.
  2. Turn the headlamp switch ON.
  3. Select HIGH at the dimmer switch.

Do the high beam headlamps come on?

--

System OK

Go to Step 2

2

Probe the WHT (68) wire at the forward lamp interface connector with a test lamp.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 3

3

Probe the WHT (68) 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 (68) wire between the headlamp dimmer switch and the forward lamp interface connector.

Is the repair complete?

--

Go to Step 1

--

5

Replace the headlamp dimmer switch.

Is the repair complete?

--

Go to Step 1

--

6

Refer to the coach manufacturer's repair manual in order to diagnose and repair the system.

Is the repair complete?

--

System OK

--