Hands-Free Cellular Phone System
DTC U0164: A/C CAN TimeoutCAUTION:
- If DTC U0164 is set, be sure to diagnose the CAN bus line.
- When replacing the ECU, always check that the communication circuit is normal.
DIAGNOSTIC FUNCTION
If the signal from A/C-ECU cannot be received, the hands free module sets the DTC U0164.
PROBABLE CAUSES
- The CAN bus line may be defective.
- The A/C-ECU may be defective.
- The hands free module may be defective.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958. Refer to "How to connect the Scan Tool (M.U.T.-III)." Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q : Is the CAN bus line found to be normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to Controller Area Network, Diagnosis).
STEP 2. Using scan tool MB991958, read the A/C diagnostic trouble code.
Check if DTC is set to the A/C-ECU.
Q : Is the DTC set?
YES : Troubleshoot the A/C (Refer to Heater and A/C and Ventilation, Automatic A/C Diagnosis). Diagnostic Trouble Code Descriptions
NO : Go to Step 3.
STEP 3. Recheck for diagnostic trouble code.
Check again if the DTC is set to the hands free module.
1. Erase the DTC.
2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
3. Check if DTC is set.
Q : Is the DTC set?
YES : Replace the hands free module.
NO : The trouble can be an intermittent malfunction (Refer to General (Body and Chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).