B1611

B1611-AMBIENT LIGHT SENSOR INPUT CIRCUIT HIGH (ATC)





For a complete wiring diagram Refer to Diagrams/Electrical.

- When Monitored:

With the ignition on.

- Set Condition:

If the Ambient Light Sensor input is out of range toward the high voltage threshold.





NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Refer to HVAC System Test (ATC) for stored DTC test procedures. HVAC System Test (ATC)

Diagnostic Test

1.CHECK (L24) AUTO HEADLAMPS SIGNAL CIRCUIT VOLTAGE





Turn the ignition off.

Disconnect the Sun Sensor harness connector.

Turn the ignition on.

Measure the voltage of the (L24) Auto Headlamps Signal circuit.

What voltage is present?

Above 5.2 Volts

- Go To 2

4.8 Volts to 5.2 Volts

- Go To 3

Below 4.8 Volts

- Go To 5

2.CHECK (L24) AUTO HEADLAMPS SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE





Turn the ignition off.

Disconnect the A/C Heater Control C1 harness connector.

Turn the ignition on.

Measure the voltage of the (L24) Auto Headlamps Signal circuit.

Is the voltage above 0.2 volts?

Yes

- Repair the (L24) Auto Headlamps Signal circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

3.CHECK (G939) SUN SENSOR RETURN CIRCUIT FUNCTION





Turn the ignition off.

Connect a jumper wire between the (L24) Auto Headlamps Signal circuit and the (G939) Sun Sensor Return circuit in the Sun Sensor harness connector.

Turn the ignition on.

With the scan tool in HVAC, select Data Display and read the Ambient Light Sensor voltage.

Is the voltage below 0.2 volts?

Yes

- Replace the Sun Sensor.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 4

4.CHECK (G939) SUN SENSOR RETURN CIRCUIT FOR AN OPEN





Turn the ignition off.

Disconnect the A/C Heater Control C1 harness connector.

Measure the resistance of the (G939) Sun Sensor Return circuit between the Sun Sensor harness connector and the A/C Heater Control C1 harness connector.

Is the resistance below 5.0 ohms?

Yes

- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Repair the (G939) Sun Sensor Return circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

5.CHECK (L24) AUTO HEADLAMPS SIGNAL CIRCUIT FOR AN OPEN





Turn the ignition off.

Disconnect the A/C Heater Control C1 harness connector.

Measure the resistance of the (L24) Auto Headlamps Signal circuit between the Sun Sensor harness connector and the A/C Heater Control C1 harness connector.

Is the resistance below 5.0 ohms?

Yes

- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Repair the (L24) Auto Headlamps Signal circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test