Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Inspection Procedure
- Check voltage between terminal ACMG of ECM connector and body ground.
PREPARATION:
Remove the ECM with connector still connected.
CHECK:
- Start the engine.
- Push AUTO SW.
- Measure voltage between terminal ACMG of ECM connector and body ground when A/C switch is ON and OFF.
OK:
A/C VOLTAGE SPECIFICATIONA/C switch Voltage ON 10 - 4 V OFF 0 V Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- OK : Go to step 3 .
- NG : Go to next step.
- Check magnetic clutch relay.
PREPARATION:
Remove magnetic clutch relay from engine room J/B.
CHECK:
Check continuity between each pair of terminals shown below of magnetic clutch relay.
OK:
TESTER CONDITION SPECIFICATIONTester connection Specified condition 1 - 2 62.5 - 90.9 Ω 3 - 5 No continuity PREPARATION:
Apply battery positive voltage between terminals 1 and 2.
CHECK:
Check continuity between terminals 3 and 5.
OK:
Continuity exists
- NG : Replace magnetic clutch relay.
- OK : Go to next step.
- Check A/C compressor magnetic clutch.
PREPARATION:
Disconnect magnetic clutch connector.
CHECK:
Connect positive (+) lead connected to battery to magnetic clutch connector terminal 3.
OK:
Magnetic clutch is energized.
- NG : Repair or replace A/C compressor magnetic clutch.
- OK : Go to next step.
- Check harness and connector between magnetic clutch relay and ECM (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
).
- NG : Repair or replace harness or connector.
- OK : Go to next step.
- Check harness and connector between ECM and A/C compressor (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE
).
- NG : Repair or replace harness or connector.
- OK : Check and replace ECM and A/C ECU.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.