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.
DTC B1422/22: Compressor Lock Sensor Circuit: Procedure
- CHECK CAN COMMUNICATION SYSTEM
- Connect the Techstream to DLC3.
- Turn the ignition switch to ON.
- Turn the Techstream on.
- Select "Communication Bus Check"
OK
All ECUs and sensors connected to the CAN communication system are displayed.
RESULTResult Proceed to CAN system is normal A CAN system is abnormal B
B → See step 5
A: Go to next step
- CHECK AIR CONDITIONING AMPLIFIER
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Remove the air conditioning amplifier with the connectors still connected. Refer to REMOVAL .
- Using an oscilloscope, check the waveform.COMPRESSOR LOCK SIGNAL
Terminal Name LOCK - SG-2 Tester Range 200 mV/DIV., 10 ms./DIV. Condition Engine is running
Blower switch LO
A/C switch ONRESULTResult Proceed to NG A OK (When troubleshooting according to Problem Symptoms Table) B OK (When troubleshooting according to the DTC output) C - Remove the air conditioning amplifier.
B → See step 6
C → See step 7
A: Go to next step
- INSPECT AIR CONDITIONING COMPRESSOR (LOCK SENSOR)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the D39 air conditioning compressor connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 1 (SSR+) - 2 (SSR-) 20°C (68°F) 165 to 205 Ω - Reconnect the air conditioning compressor connector.
NG → See step 8
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - AIR CONDITIONING COMPRESSOR)
- Disconnect the H24 air conditioning amplifier connector.
- Disconnect the D39 air conditioning compressor connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition H24-8 (LOCK) - D39-1 (SSR+) Always Below 1 Ω H24-13 (SG-2) - D39-2 (SSR-) Always Below 1 Ω H24-8 (LOCK) or D39-1 (SSR+) - Body ground Always 10 kΩ or higher H24-13 (SG-2) or D39-2 (SSR-) - Body ground Always 10 kΩ or higher - Reconnect the air conditioning amplifier connector.
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK → See step 7
- GO TO CAN COMMUNICATION SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING
- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
- REPLACE AIR CONDITIONING AMPLIFIER. Refer to REMOVAL
- REPLACE AIR CONDITIONING COMPRESSOR (LOCK SENSOR). Refer to REMOVAL
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.