On-Board Diagnostic System

ON-BOARD DIAGNOSTICS LH3.2 MFI and EZ-129K DI

Each of the control modules incorporates Volvo Diagnostics, which continuously monitor the input and output signals. In the event of a fault which affects the exhaust emission levels, the ICM will activate the MIL (Check engine lamp) on the combined instrument. Fault tracing may be carried out either with the ST or by means of the three test modes, which can be accessed through socket 2 (MFl) or 6 (DI) on DLC "A".

Diagnostic test modes:
^ Mode 1 Displays Diagnostic Trouble Codes (DTCs) (if any are stored)
^ Mode 2 Acknowledges component operation
^ Mode 3 Operates components in a given, predetermined sequence