DTC B2797: Communication Malfunction No. 1
NOTE:
DTC B2797 may be caused by excessive noise interference, defective transponder key amplifier, wiring or ECM.
- Check System For Noise Interference
Insert registered master key into ignition lock cylinder. Using an oscilloscope or scan tool, check for noise in the scope pattern at ECM connector E8 terminal No. 4 (Black/Red wire). This is the Black/Red wire between ECM and the transponder key amplifier. For ECM terminal identification, See Figure. Transponder key amplifier is located near upper steering column bracket and ECM is located behind glove box. See Figure. Noise will be displayed as indicated in the scope pattern. See Fig 1. If no noise is detected, go to next step. If noise is detected, find where noise interference is coming from and repair as necessary. - Replace Transponder Key Amplifier
Replace transponder key amplifier. See TRANSPONDER KEY AMPLIFIER under REMOVAL & INSTALLATION. Check system operation. If system operates normally after replacing original transponder key amplifier, no further testing is required at this time, as the original transponder key amplifier was defective. If system still does not operate normally after replacing original transponder key amplifier, go to next step. - Replace ECM. See ENGINE CONTROL MODULE (ECM) under REMOVAL & INSTALLATION. Ensure ignition keys are registered to the ECM. See IGNITION KEY REGISTRATION under PROGRAMMING.