With Manufacturer's Scan Tool
Fuel injectors, checking
Special tools and equipment
- V.A.G 1551 Scan Tool (or VAG 1552 mobile scan tool) with VAG 1551/3 cable
- VAG 1598/31 test box
- VAG 1526 multimeter or VAG 1715 multimeter
- VAG 1527 voltage test lamp
- VAG 1594 connector test kit
- Wiring diagram
Test requirements
- Engine speed (RPM) sensor must be working properly. Engine Speed (RPM) Sensor, Checking
- Fuel Pump (FP) relay must be working properly.
- Fuses no.28 and 32 must be OK.
Checking Resistances of Fuel Injectors
- Test resistance of fuel injectors between terminals.
Specification: 13.5 - 15.5 Ohms
NOTE: Resistance value is valid at approx. 20°C. At higher temperatures, the value will rise approx. 4 - 6 Ohms.
If specified value is not obtained:
- Replace faulty fuel injector.
Checking voltage supply
- Pull connectors (1) off connection (2) of all fuel injectors.
- Connect diode test lamp to connector of tested fuel injector terminal 1 and Ground (GND).
- Switch on starter and test voltage supply for fuel injector.
LED must light.
If LED does not light up:
- Switch ignition off.
- Check for breaks in wire between 2-way connector terminal 1 Fuel Pump (FP) relay (J17) (see wiring diagram).
Wire resistance: max. 1.5 Ohms
Checking Activation and Voltage Supply
- Pull connectors (1) off connection (2) of all fuel injectors.
- Use auxiliary wires from VAG 1594 to connect diode test lamp VAG 1527 to connector terminals of fuel injector to be tested.
- Switch on starter and test activation of fuel injector.
LED should flicker.
NOTE: The LEDs in the test lamp consume very little power and do not go out completely but rather glow a little longer and become brighter between activations by the Engine Control Module (ECM).
If LED does not flicker:
- Switch ignition off.
- Connect VAG 1598/31 test box to control module wiring harness. Engine Control Module (ECM) is not connected.
- Use wiring diagram to check wires between test box and harness connector for open circuits or short circuits to Ground (GND) or B+.
fuel injector 1: Terminal 2 + socket 96
fuel injector 2: Terminal 2 + socket 112
fuel injector 3: Terminal 2 + socket 88
fuel injector 4: Terminal 2 + socket 97
fuel injector 5: Terminal 2 + socket 113
fuel injector 6: Terminal 2 + socket 89
Wire resistance: max. 1.5 Ohms
If there is no DTC in wire connection:
- Replace Engine Control Module (ECM).