DTC B1451: Compressor Solenoid Circuit [06/2018 - 08/2020]: Procedure
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- INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY
*a Front view of wire harness connector
(to Cooler Compressor Assembly)- Disconnect the C35 cooler compressor assembly connector.
- Connect an oscilloscope to terminal C35-2 (SOL+) and body ground and check the waveform.
Item Content Tool Setting 5 V/DIV., 500 μs./DIV. Condition - Engine running
- Blower switch: LO
- A/C switch: On
OK
Waveform is similar to that shown in the illustration.
Result
Proceed to OK NG
Result:
OK
REPLACE COOLER COMPRESSOR ASSEMBLY. Refer to REMOVAL [06/2018 - 08/2021]
Result:
NG
See step 2
- CHECK HARNESS AND CONNECTOR (COOLER COMPRESSOR ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)
- Disconnect the G39 air conditioning amplifier assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition C35-2 (SOL+) - G39-3 (SOL+) Always Below 1 Ω C35-2 (SOL+) or G39-3 (SOL+) - Other terminals and body ground Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to REMOVAL [06/2018 - 08/2020]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR