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.
Check Keyless Entry Control Module
- CHECK KEYLESS ENTRY CONTROL MODULE
.
Read the DTC of body integrated unit using Subaru Select Monitor.
NOTE: For detailed operation procedures, refer to "Application help".Is DTC U1500 "KEYLESS UART COM. MALFUNCTION" displayed?
Yes: Go to 2
No: Keyless entry control module is normal.
- CHECK POWER SUPPLY
.
- Disconnect the keyless entry control module connector.
- Measure the voltage between keyless entry control module connector and chassis ground.
Connector & terminal
Model without tire pressure monitoring system
(R80) No. 4 (+) - Chassis ground (-):
Model with tire pressure monitoring system
(R221) No. 6 (+) - Chassis ground (-):
Is the voltage 10 V or more?
Yes: Go to 3
No: Check the harness for open or short circuits between the keyless entry control module and the fuse.
- CHECK GROUND CIRCUIT
.
Measure the resistance between keyless entry control module connector and chassis ground.
Connector & terminal
Model without tire pressure monitoring system
(R80) No. 7 - Chassis ground:
Model with tire pressure monitoring system
(R221) No. 5 - Chassis ground:
Is the resistance less than 10 Ω?
Yes: Go to 4
No: Repair or replace the harness.
- CHECK KEYLESS ENTRY CONTROL MODULE CIRCUIT
.
- Disconnect the body integrated unit connector.
- Check the harness between keyless entry control module and body integrated unit.
Connector & terminal
Model without tire pressure monitoring system
(i171) No. 11 - (R80) No. 3:
Model with tire pressure monitoring system
(i171) No. 11 - (R221) No. 11:
Is harness normal?
Yes: Replace the keyless entry control module.
No: Repair or replace the harness.
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.
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