Malfunction Indicator Lamp (MIL)

Check Malfunction Indicator Lamp (MIL) In Instrument Cluster

Installation position of emissions MIL

Version A:

Version B:

Meaning of emissions MIL
The Malfunction Indicator Lamp (MIL) lights up when emissions relevant malfunctions are recognized by the Engine Control Module (ECM).

NOTE: The Malfunction Indicator Lamp (MIL) can blink or remain lit continuously. DTC memory must be checked in each case. Reading Diagnostic Trouble Codes
- Blinking: There is a malfunction that causes damage to the catalytic converter in this driving condition. In this case, vehicle must only be driven at reduced power.
- Continuously lit: There is a malfunction that causes increased emissions. Check DTC memory for Motronic control module.
- DTC memory must still be checked if there are driveability problems or the customer has made a complaint but the MIL is not lit, because malfunctions can be stored without causing the MIL to light immediately.

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirement





- The respective fuses of Malfunction Indicator Lamp (MIL) -K83- must be OK.

Test sequence
- Switch on ignition:emissions MIL must light up.

If emissions MIL does not light up when ignition is switched on:
- Switch ignition off.
- Check wire from ECM to emissions MIL as follows:
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test

Vehicles with engine code AEG
- Bridge sockets 2 + 17 of test box with the respective adapter cables.

Vehicles with engine code AVH and AZG
- Bridge sockets 2 + 47 of test box with the respective adapter cables.

Continuation for all vehicles
- Switch on ignition: emissions MIL must light up.

If Malfunction Indicator Lamp (MIL) does not light up:
- Switch ignition off.
- Remove instrument cluster.
- Check wire connection from Engine Control Module (ECM) to Malfunction Indicator Lamp (MIL) -K83- according to wiring diagram.
- Erase DTC memory of Engine Control Module (ECM). Clearing Diagnostic Trouble Codes
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If no malfunctions are detected in wire from Engine Control Module (ECM) to Malfunction Indicator Lamp (MIL):
- Replace Motronic Engine Control Module (ECM) -J220-.

If emissions MIL lights up when ignition is switched on:
- Start engine and let run at idle: Emissions MIL must go out after a few seconds.

If Malfunction Indicator Lamp (MIL) does not go out:
- Switch ignition off.
- Remove instrument cluster.
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test

Vehicles with engine code AEG
- Check wire connection between test box socket 17 and instrument cluster for short circuit to Ground (GND) according to wiring diagram.

Vehicles with engine code AVH and AZG
- Check wire connection between test box socket 47 and instrument cluster for short circuit to Ground (GND) according to wiring diagram.

Continuation for all vehicles
- Erase DTC memory of Engine Control Module (ECM). Clearing Diagnostic Trouble Codes
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If no malfunctions are detected in wire from Engine Control Module (ECM) to Malfunction Indicator Lamp (MIL):
- Replace Motronic Engine Control Module (ECM) -J220-.