B1605

B1605-RIGHT SOLAR SENSOR CIRCUIT HIGH







Theory of Operation

The HVAC A/C Heater Control uses a variety of sensors to adjust HVAC operation to obtain optimal performance. These sensors are continuously monitored by the A/C Heater Control to assure that they are in range. If those sensors fall out of predetermined ranges a DTC will set.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
If the Left Sun Sensor Signal 2 input voltage is greater than 4.5 volts for period of 60 seconds. This DTC has a de-maturing time of 10 seconds. If the DTCs status changes from active to stored, the DTC will stay in memory for 100 ignition cycles.





Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

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

NOTE: It can take up to 60 seconds or more for this DTC to mature.

Is this DTC active?

Yes

- Go To 2

No

- Go To 6

2. CHECK THE SUN SENSOR




1. Turn the ignition off to the lock position.
2. Disconnect the Sun Sensor harness connector.
3. Connect a jumper wire between the (G139) Sun Sensor Signal 2 circuit and the (C121) Sensor Ground circuit in the Sun Sensor harness connector.
4. Ignition on, engine not running.
5. With the scan tool, read HVAC DTCs.

Did the DTC B1604-Right Solar Sensor Circuit Low set or is the Sun Sensor voltage below 0.5 of a volt?

Yes

- Replace the Sun Sensor.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 3

3. CHECK THE (G139) SUN SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off to the lock position.
2. Disconnect the jumper wire in the Sun Sensor harness connector.
3. Disconnect the A/C Heater Control harness connector.

NOTE: Check connectors - Clean/repair as necessary.

4. Ignition on, engine not running.
5. Check the voltage of the (G139) Sun Sensor Signal 2 circuit.

Is there any voltage present?

Yes

- Repair the (G139) Sun Sensor Signal 2 circuit for an short to voltage.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 4

4. CHECK THE (G139) SUN SENSOR SIGNAL 2 CIRCUIT FOR AN OPEN




1. Turn the ignition off to the lock position.
2. Measure the resistance of the (G139) Sun Sensor Signal 2 circuit between the A/C Heater Control harness connector and the Sun Sensor harness connector.

Is the resistance above 1.0 Ohm?

Yes

- Repair the (G139) Sun Sensor Signal 2 circuit for an open or high resistance.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Go To 5

5. CHECK THE (C121) SENSOR GROUND CIRCUIT FOR AN OPEN




1. Measure the resistance of the (C121) Sensor Ground circuit between the A/C Heater Control harness connector and the Sun Sensor harness connector.

Is the resistance above 1.0 Ohm?

Yes

- Repair the (C121) Sensor Ground circuit for an open or high resistance.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

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

6. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. With the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.
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. Wiggle the wiring and connectors while checking for shorted and open circuits.

Were there any problems found?

Yes

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

No

- Test complete.