TT Quattro Roadster L4-1.8L Turbo (AMU) (2002)
Malfunction Indicator Lamp: Testing and Inspection
Malfunction Indicator Lamp -K83, Testing
Function test:
-
Switch on ignition:
MIL must light up.
If MIL does not light up when ignition is switched on:
-
Check wire from ECM to MIL as follows:
Cause:
Corrective action:
MIL is not being activated or is not lighting
-
Switch off ignition.
due to an open circuit.
-
Connect VAG1598/31 test box. See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Scan Tool Testing and Procedures/Scan Tool Testing/Scan Tool
Connecting and Initial Checks/Wiring and Component Testing Using VAG1598/31 Test Box
-
Bridge sockets 2 and 47 of test box.
-
Switch on ignition.
MIL must light up. If MIL lights up:
Replace Engine Control Module (ECM)
If MIL does not light up:
-
Switch off ignition.
-
Locate short circuit or open circuit from ECM to MIL (instrument cluster) and repair.
-
If no malfunctions are found in wire to MIL:
Malfunction cause
-
Instrument cluster faulty, replace instrument cluster
If MIL does not light up when ignition is switched on, continue test as follows:
-
Start engine and let run at idle:
MIL must go out after a few seconds.
If MIL does not go out:
-
Check DTC Memory.
If there no DTCs are stored:
Cause:
Corrective action:
Malfunction Indicator Lamp (MIL) is
-
Switch off ignition.
constantly activated due to a short circuit
-
Connect VAG1598/31 test box. See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Scan Tool Testing and Procedures/Scan Tool Testing/Scan Tool
Connecting and Initial Checks/Wiring and Component Testing Using VAG1598/31 Test Box
to Ground (GND).
-
Measure wire resistance between socket 47 of test box and vehicle Ground (GND). Specification:
infinite Ohm (Infinity)
If specified value is not obtained:
Short circuit to Ground (GND) in activation wire from ECM to MIL.
-
Locate malfunction using wiring diagram and repair.
If specified value of infinite Ohm is obtained, and no short circuit to Ground (GND) is found:
Malfunction cause
Engine Control Module (ECM) faulty replace ECM.