Pinout Values and Diagnostic Parameters

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: TERMINALS OF ECU

1. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY





(a) Disconnect the E36, E35 and z45 air conditioning amplifier connectors.

(b) Measure the voltage and resistance according to the value(s) in the table below.





If the result is not as specified, there may be a malfunction on the wire harness side.

(c) Reconnect the E36, E35 and z45 air conditioning amplifier connectors.

(d) Measure the voltage according to the value(s) in the table below.









If the result is not as specified, the air conditioning amplifier assembly may have a malfunction.

(e) Using an oscilloscope, check waveform 1.





A/C Compressor Lock Sensor Signal





HINT
When the rear blower level is increased, the duty ratio changes accordingly.

(f) Using an oscilloscope, check waveform 2.





Blower Motor Control Signal





HINT
When the blower level is increased, the duty ratio changes accordingly.

(g) Using an oscilloscope, check waveform 3.





Rear Blower Motor Control Signal





HINT
When the rear blower level is increased, the duty ratio changes accordingly.

2. CHECK DISPLAY AND NAVIGATION MODULE DISPLAY





(a) Disconnect the F53 display connector.

(b) Measure the resistance and voltage according to the value(s) in the table below.





If the result is not as specified, there may be a malfunction on the wire harness side.

3. CHECK NO. 2 AIR CONDITIONING CONTROL ASSEMBLY





(a) Disconnect the E55 switch connector.

(b) Measure the resistance and voltage according to the value(s) in the table below.





If the result is not as specified, there may be a malfunction on the wire harness side.

4. CHECK MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)





(a) Disconnect the 2A, 2D, E1, E2 and E3 ECU connectors.

(b) Measure the voltage and resistance according to the value(s) in the table below.





If the result is not as specified, there may be a malfunction in the wire harness.