B10EA

B10EA-BLOWER MOTOR CONTROL CIRCUIT HIGH





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The A/C Heater Control constantly monitors the Blower Control circuit to the Blower Module for proper operation. If the voltage on that circuit drops below or rises above a predetermined value, a DTC will set.

- When Monitored:
With the ignition on.

- Set Condition:
If the Blower Control circuit voltage is greater than a calibrated value for the period of 30 seconds.





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 30 seconds or more for this DTC to mature.

Is this DTC active?

Yes

- Go To 2

No

- Go To 6

2. CHECK THE (C56) BLOWER CONTROL CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off to the lock position.
2. Disconnect the Blower Module 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 (C56) Blower Control circuit.

Is there any voltage present?

Yes

- Repair the (C56) Blower Control circuit for an short to voltage.
- Perform HVAC VERIFICATION TEST HVAC Verification Test.

No

- Go To 3

3. CHECK THE (C56) BLOWER CONTROL CIRCUIT FOR AN OPEN




1. Turn the ignition off to the lock position.
2. Measure the resistance of the (C56) Blower Control circuit between the A/C Heater Control harness connector and the Blower Module harness connector.

Is the resistance above 1.0 Ohm?

Yes

- Repair the (C56) Blower Control circuit for an open.
- Perform HVAC VERIFICATION TEST HVAC Verification Test.

No

- Go To 4

4. CHECK THE (Z911) GROUND CIRCUIT FOR AN OPEN




1. Using a 12-volt test light connected to 12-volts, check the (Z911) Ground 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

- Repair the (C56) Blower Control circuit for an open.
- Perform HVAC VERIFICATION TEST HVAC Verification Test.

No

- Go To 5

5. CHECK THE BLOWER MODULE
1. Turn the ignition off to the lock position.
2. Replace the Blower Module.
3. Perform HVAC VERIFICATION TEST HVAC Verification Test.

Did the DTC reset during or after the HVAC Verification Test?

Yes

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

No

- Test complete.

6. 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. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, partially broken wires.
4. Check the connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
5. Wiggle the wiring and connectors while checking for shorted and open circuits.
6. 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 HVAC VERIFICATION TEST HVAC Verification Test.

No

- Test complete.