Diagnostic trouble code (DTC) information

WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.

IMM-333 VGLA control circuit

Condition

Fig 1: Identifying Immobilizer Control Module

Courtesy of VOLVO CARS OF NORTH AMERICA.

During the first two seconds after ignition the immobilizer control module checks that the connection to the VGLA control module is fault free. If the control module detects a fault diagnostic trouble code (DTC) IMM-333 is stored.

The diagnostic trouble code (DTC) is erased when the counter value is one.

Information

Cars with an alarm have an LED in the center of the dashboard. It flashes slowly when the ignition is switched off and the alarm is activated (flash frequency 1 Hz).

In certain markets even cars without alarm can have a LED on the center of the dashboard which blinks slowly when the ignition is switched off (flashing frequency 1 Hz). This is to indicate that the immobilizer is active and that the car is immobilized. This function is retained only if the VGLA control module parameters"ALARM" respectively "IMMO" are set to "OFF" respectively "ON".

In both the above cases if the VGLA system parameter "IMMO"is set to "ON" information about certain immobilizer system functions can be obtained from observing the LED behavior when the ignition is switched on. This occurs by the VGLA control module checking the status of the cable connecting the immobilizer control module with the VGLA control module.

A fault in the immobilizer system which means that the engine cannot be started, for example failure to identify ignition key or an unrecognized key used, causes the LED to flash fast (flash frequency 4 Hz) for 15 seconds after ignition.

Possible Source

The cable between immobilizer control module #7 and VGLA #A:11 is short-circuited to ground. Diagnostic trouble code (DTC) GLA-454 can be stored in the VGLA system with this fault.
The cable between immobilizer control module #7 and VGLA control module #A:11 is short-circuited to supply voltage.
Open-circuit in cable between immobilizer control module #7 and VGLA control module #A:11

Fault symptom[s]

If the LED is installed and the parameter "IMMO" in the VGLA system iset "ON" the LED flashes at 4 Hz for 15 seconds after ignition if the short-circuited to positive when the ignition is switched on.
Other fault types and VGLA settings have no fault symptoms.