Malfunction Indicator Lamp (MIL) Functional, Checking

Malfunction Indicator Lamp (MIL) Function, Checking

- Switch ignition on.
MIL must light up.

If MIL does not light:
- Switch ignition off.







- Connect VAG1598/19 test box to ECM harness connector and connect jumper wire between sockets 09 and D11 (Ground). Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/VAG1598/19 Test Box, Connecting" Testing and Inspection
- Switch ignition on.
MIL must light up.

If MIL now lights (with jumper wire connected):
- Replace Engine Control Module (ECM).
- Generate readiness code. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Code)/Generating, Readiness Code" Testing and Inspection


If MIL still does not light:
- Switch ignition off.
- Check MIL bulb.

If MIL bulb is OK:
- Check wiring for open or short circuit between ECM/test box socket C9 and instrument cluster.

If wiring is OK:
- Check voltage supply from instrument cluster.

If the MIL lights up when the engine is running, and only P1690/18098 is stored in DTC memory:
- Stop engine (switch ignition off).
- Disconnect ECM harness connector.
- Switch ignition on.

If MIL stays on:
- Check wiring for short circuit to Ground between ECM connector terminal C9 and instrument cluster.