Checking components and wiring
- Ignition off.CAUTION:
The blower fan motor power unit is very sensitive to short-circuits and excess current. Do not damage the power unit when taking readings.
Take readings with the power unit connector disconnected when checking the wiring.
Check if the fuse for the climate control module (CCM) is defective. If the fuse is defective, check:
- the signal cable between the fuse and the power unit terminal #A2. Check for a short-circuit to ground
- the signal cable between the power unit terminal #B2 and the blower fan motor positive terminal. Check for a short-circuit to ground.
Check the control signal cable between control module terminal #A3 and power unit terminal #A1. Check for a short-circuit to supply voltage.
Check the diagnostic signal cable between control module terminal #A2 and power unit terminal #A3. Check for an open-circuit. Check for a short-circuit to ground.
Remedy as necessary.
Other information:
- To access or replace the control module, see Dashboard environment panel (including climate control module (CCM)), replacing
- To access the control module or connect the breakout box, see Connecting the breakout box
- To access or replace the power unit, see Blower fan motor / power unit, replacing
- With the ignition on and the power unit connector disconnected, the voltage between power unit connector terminal #A2 (control module side) and ground must be approximately 13.5 V
- For other values, see Signal specification
- See Checking wiring and terminals .
- Continue
Refer to Verification