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.
Retrieving Trouble Codes
Codes from multiplex self-diagnostic system are retrieved through Data Link Connector 2 (DLC2). With key on engine off, connect jumper wire between DLC2 terminal E1 and terminal Tc. See Fig 1. If any code is present, perform test(s) in order given. See MULTIPLEX TROUBLE CODE DEFINITION table.
| Code No. | Diagnosis Problem | Perform Test No. |
| 11 | Communication From Driver's Door ECU to Body ECU Is Cut Off | TEST NO. 1 |
| 12 | Communication From Front Passenger Door ECU to Body ECU Is Cut Off | TEST NO. 2 |
| 13 | Communication From Tilt/Telescopic ECU to Body ECU Is Cut Off | TEST NO. 3 |
| 14 | Communication Circuit Is Shorted To Battery Voltage | TEST NO. 4 |
| 15 | Communication Circuit Is Shorted To Ground | TEST NO. 4 |
| 21 | Power Window Master Switch Stays On, Or Is In Operation | TEST NO. 5 |
| 22 | Driver's Key Lock & Unlock Switch Stays On, Or Is In Operation | TEST NO. 6 |
| 22 | Driver's Memory Switch Stays On, Or Is In Operation | TEST NO. 6 |
| 22 | Shoulder Belt Adjust Switch Stays On, Or Is In Operation | TEST NO. 6 |
| 31 | Front Passenger Door Lock Control Switch Stays On, Or Is In Operation | TEST NO. 7 |
| 31 | Front Passenger Door Key Lock & Unlock Switch Stays On, Or Is In Operation | TEST NO. 7 |
| 41 | Luggage Compartment Door Opener Switch Stays On, Or Is In Operation | TEST NO. 8 |
| 41 | Luggage Compartment Door Key Switch Stays On, Or Is In Operation | TEST NO. 8 |
| 51 | Mirror Control Switch Stays On, Or Is In Operation | TEST NO. 9 |
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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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