[Previous][Next]
DTC B240D: Front antenna (indoor) open
 
 
cautionWhen replacing the ECU, always check that the communication circuit is normal.
 
 
DIAGNOSTIC FUNCTION
If an open circuit is detected in the inside transmission antenna (front), the DTC is set.
 
 
TECHNICAL DESCRIPTION (COMMENT)
When the electric motor switch is pressed, or when the antenna open circuit detection request is received from the diagnosis function, the failure is detected.
 
 
TROUBLESHOOTING HINTS
  • Malfunction of the inside transmission antenna assembly (front)
  • Malfunction of the KOS-ECU
  • Damaged wiring harness and connectors
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Check of short to power supply, short to ground, and open circuit in INFP, INFG line between the inside transmission antenna assembly (front) connector and the KOS-ECU connector.
Is the check result normal?
Go to Step 2.
Repair the connectors or wiring harness.
 
STEP 2. Keyless operation system communication test
Check that the communication with the inside transmission antenna assembly (front) is normal (Refer to Antenna Test ).
Antennas to be checked
  • Front antenna (indoor)
OK: Normal is displayed.
Is the check result normal?
Go to Step 3.
Replace the inside transmission antenna assembly (front).
 
STEP 3. Check whether the diagnostic trouble code is set again.
(1) Erase the DTC.
(2) Turn the power supply mode of the electric motor switch from OFF to ON.
(3) Check if the DTC is set.
(4) Turn the power supply mode of the electric motor switch from ON to OFF.
Is the DTC set?
Replace KOS-ECU and register the ID codes (Refer to ).
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Deal with Intermittent Malfunction ).