Chart 5, No Blower Operation
Based on a signal from the BCM, the programmer sends a variable voltage signal to the power module. The signal is then amplified and sent to the blower motor. The programmer monitors the blower motor voltage so that the signal can be adjusted to achieve the desired blower motor speed.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- This step checks to see if the fault is due to the blower signal circuit to the programmer or the circuits used for blower control.
- This step checks to see if the fault in blower control is due to a short in circuit No. 754, including the programmer, or the rest of the control circuits.
- This step checks to see if the fault in blower control is due to an open circuit No. 754 or the rest of the control circuits.
- This step checks to see if the fault in the blower control is due to an open blower motor ground, including the blower motor, or the rest of the control circuits.
- This step checks to see if the fault in the blower control is due to an open in the power module feed circuit or a short in the blower motor feed circuit, including poor terminal contact and excessive current draw from the blower motor.
- This step checks to see if the fault in the blower signal is due to a short in circuit No. 760, the programmer, or the BCM.