With Manufacturer's Scan Tool

Malfunction Indicator Lamp (MIL) Checking

Checking function

- Switch ignition on.
MIL must light up.

If MIL does not light when ignition is switched on, check wiring to MIL as follows:

Cause: Corrective action:
MIL is not triggered, or -Switch ignition off
does not light, due to -Connect VAG1598/22 test box
faulty wiring or open circuit. -Connect jumper wire to bridge test box sockets 2 and 17
-Switch ignition on
-MIL must light up

If MIL does not light
-Switch ignition off
-Check bulb for MIL

If bulb is OK:
-Check wiring for open circuit between MIL and Motronic ECM -J220- using applicable wiring diagram.

If wiring is OK:
Malfunction: -Motronic ECM -J220- is faulty; replace.

If MIL lights up when ignition is switched on, continue checking as follows:
- Start engine and let run at idle.
MIL must go out after a few seconds.

If MIL does not go out:
- Check Diagnostic Trouble Code (DTC) memory.

If there are no malfunctions stored in DTC memory:

Cause: Corrective action:
MIL is triggered continuously -Switch ignition off.
due to short circuit to Ground. -Connect VAG1598122 test box.
-Check resistance between test box socket 17 and vehicle Ground,
specified value: Infinity Ohm (no continuity)
If the specified value is not obtained:
-Check for short circuit to Ground in wiring from Motronic Engine Control
Module (ECM) - J220- to MIL.
-Trace malfunction using applicable wiring diagram and repair as necessary
If there is no continuity, and no short circuit to Ground:
Malfunction: Motronic ECM -J220- is faulty; replace