B1034

B1034-INFRARED TEMPERATURE SENSOR INPUT CIRCUIT LOW

- When Monitored:
With the ignition on.

- Set Condition:
When the Infrared (IR) Temperature Sensor Pulse Width Modulated (PWM) signal to the A/C Heater Control is less than 9.5% for a continuous period of 123 msec. If the A/C Heater Control detects a valid PWM signal, the DTC will change from active to stored and will stay stored for 100 ignition cycles.

Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. HVAC Pre-Diagnostic Troubleshooting Procedure.

1. CHECK IF DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Go To 10

2. IDENTIFY THE VEHICLE
1. Pick below what best describes the vehicle you are working on.

JS27 Two Door

- Go To 3

JS41 Four Door

- Go To 6

3. CHECK THE (F202) IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN (JS27)

1. Turn the ignition off to the lock position.
2. Disconnect the Infrared Sensor harness connector.
3. Ignition on, engine not running.
4. With a test light connected to ground, check the (F202) Ignition Switch Output (Run-Start) circuit.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the (F202) Ignition Switch Output (Run-Start) circuit for an open.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

4. CHECK THE (C83) IR SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND (JS27)

1. Turn the ignition off to the lock position.
2. Disconnect the A/C Heater Control harness connector.
3. Measure the resistance between ground and the (C83) IR Sensor Signal circuit.

Is the resistance below 100k Ohms?

Yes

- Repair the (C83) IR Sensor Signal circuit for a short to ground.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 5

5. CHECK THE (C83) IR SENSOR SIGNAL CIRCUIT FOR AN OPEN (JS27)

1. Turn the ignition off to the lock position.
2. Disconnect the Infrared Sensor harness connector.
3. Ignition on, engine not running.
4. With a test light connected to ground, check the (F202) Ignition Switch Output (Run-Start) circuit.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Go To 7

No

- Repair the (F202) Ignition Switch Output (Run-Start) circuit for an open.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

7. CHECK THE (C83) IR SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND (JS41)

1. Turn the ignition off to the lock position.
2. Disconnect the A/C Heater Control harness connector.
3. Measure the resistance between ground and the (C83) IR Sensor Signal circuit.

Is the resistance below 100k Ohms?

Yes

- Repair the (C83) IR Sensor Signal circuit for a short to ground.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 8

8. CHECK THE (C83) IR SENSOR SIGNAL CIRCUIT FOR AN OPEN (JS41)

1. Measure the resistance of the (C83) IR Sensor Signal circuit between the A/C Heater Control harness connector.

Is the resistance below 100k Ohms?

Yes

- Repair the (C83) IR Sensor Signal circuit for an open.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 9

9. CHECK THE INFRARED SENSOR
1. Replace the Infrared Sensor.
2. Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

Did the DTC reset performing the HVAC Verification Test?

Yes

- Replace and program the A/C Heater Control.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.

10. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. With the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.