35. DTC: P0646, A/C Compressor Relay Control Circuit Voltage Too Low (see Table 1-48)
Table 1-48
S/N Operation Test Results Actions
1
Connect the diagnostic instrument and adapter, and turn the
ignition switch to OFF.
Next step
Yes Go to step 4
2
Disconnect the A/C compressor relay, and turn the ignition
switch to ON. Measure the voltage between pin 30#, 85# of
the relay (power supply end) and the power supply negative
pole. Is the voltage about 12V?
No Next step
Yes
Repair or replace
harness
3
Check for open circuit or short to ground at the power supply
end of the relay.
No Go to step 2
Yes Replace relay
4
Measure the voltage between the pin 86# of the relay
(control end) and the power supply negative pole with a
multimeter. Is the voltage about 3.7V?
No Next step
Yes
Repair or replace
harness
5
Check for short to ground between the pin 86# of the relay
(control end) and the 70# of the ECU with a multimeter.
No Diagnosis help
36. DTC: P0647, A/C Compressor Relay Control Circuit Voltage Too High (see Table 1-49)
Table 1-49
S/N Operation Test Results Actions
1
Connect the diagnostic instrument and adapter, and turn the
ignition switch to OFF.
Next step
Yes Go to step 4
2
Disconnect the A/C compressor relay, and turn the ignition
switch to ON. Measure the voltage between pin 30#, 85# of
the relay (power supply end) and the power supply negative
pole. Is the voltage about 12V?
No Next step
Yes
Repair or replace
harness
3
Check for open circuit or short to ground at the power supply
end of the relay.
No Go to step 2
Yes Replace relay
4
Measure the voltage between the pin 86# of the relay
(control end) and the power supply negative pole with a
multimeter. Is the voltage about 3.7V?
No Next step
Yes
Repair or replace
harness
5
Check for short to power supply between the pin 86# of the
relay (control end) and the 70# of the ECU with a multimeter.
No Diagnosis help
To Next Page
Loading...