1.CHECK DTC. Read the DTC. Diagnostic Code(s) Display | Is DTC B2A04 displayed- (Current malfunction) | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2A04 MIC CIRCUIT | Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause. |
2.CHECK HARNESS (OPEN CIRCUIT). 1) Turn the ignition switch to OFF. 2) Disconnect the microphone connector. 3) Disconnect the DCM connector. 4) Measure the resistance between microphone connector and DCM connector. Connector & terminal (R353) No. 1 — (i271) No. 8: (R353) No. 4 — (i271) No. 14: (R353) No. 3 — (i271) No. 6: | Is the resistance 1 - or less- | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2A04 MIC CIRCUIT | Repair or replace the open circuit of harness. |
3.CHECK HARNESS (GROUND SHORT CIRCUIT). Measure the resistance between DCM connector and chassis ground. Connector & terminal (i271) No. 8 — Chassis ground: (i271) No. 14 — Chassis ground: (i271) No. 6 — Chassis ground: | Is the resistance 1 M- or more- | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2A04 MIC CIRCUIT | Repair or replace the open circuit of harness. |
4.CHECK THE CONNECTOR (SHORT CIRCUIT TO POWER SUPPLY). Measure the voltage between DCM connector and chassis ground. Connector & terminal (i271) No. 8 (+) — Chassis ground (−): (i271) No. 14 (+) — Chassis ground (−): (i271) No. 6 (+) — Chassis ground (−): | Is the voltage less than 1 V- | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2A04 MIC CIRCUIT | Repair or replace the short circuit of the harness. |
5.CHECK MICROPHONE. Confirm the microphone voice input. | | Replace the DCM. Data Communication Module | Replace the microphone. Microphone |