AM/FM Antenna short circuit to Ubat
Disconnect the AM/FM antenna power cord (white connector) from the antenna (U26). Restart the infotainment system and check if the DTC remains active. If so, the error probably depends on the antenna. Disconnect the antenna. Allow the antenna's power cord to be connected to the on-board electronic controller. Measure the wiring between ground and signal. The measurement result should be between 8 and 16 V. Check the short circuit for the remaining wiring between the antenna and the electronic controller. If the fault is not in the wiring or antenna, there is probably an internal fault in the electronic control unit.
What you'll see
The infotainment system cannot receive signals from the antenna. Very bad or no reception on the AM/FM radio.
System reaction
AMFM Might not work as expected
Diagnostic depth
When the AMFM Antenna is Short Circuited to UBAT and also EOL "System_AM/FM/FM2 Antenna type" is "ACTIVE (0x01)". When the current at antenna > 50mA. This fault will be detected during run-time. Note! Antenna supervision only works above 12.6V for the following HW assy: 2490024, 2490025, 2490026, 2551941, 2551942.
Antenna malfunction is triggered by any of the following conditions: - Faulty connector - Faulty wire harness - Faulty antenna U26