Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information ICM-U01844A

Condition
The serial number of each control module in the infotainment system is stored in the central electronic module (CEM). The stored numbers are compared with the serial numbers of the control modules at start up. If the numbers do not correspond, that particular control module is blocked and the function is not available. The blocking function for non-approved control modules is designated Infotainment Theft Protection (ITP).
The infotainment module (ICM) checks whether the integrated audio module (IAM) is on the valid list stored in the central electronic module (CEM).
The diagnostic trouble code (DTC) is stored if the control module detects that:
- Integrated Audio Module (IAM) not included in valid list.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Ignition on for at least 12 seconds.
- Battery voltage higher than 11 V.
- Infotainment Theft Protection (ITP) activated.





Substitute value
- None.

Possible source
- Replacement of invalid integrated audio module (IAM) according to the valid list stored in the central electronic module (CEM).
- Software not downloaded at replacement of control module.
- Failed or incomplete software download to control module.

Fault symptom[s]
- Radio does not operate
- CD player does not function
Hint: The following only applies to S80 (07-), V70 (08-) and XC70 (08-) manufactured before week 35, 2008: If the trouble symptom is Audio other/Audio unit (complete) not working, Audio other/Display on audio unit not working, Audio other/Other audio problems or Radio/Not working, check and troubleshoot according to: TIE TJ 18609.