2 Check wiring harness for short to B+ or to ground, or for open circuit.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Remove connector of fuel injector.
3. Connect ohmmeter to special tool 9637, pin III/15, and injector connector, pin 2.
Display: 0 - 5 ohms
4. Connect ohmmeter to special tool 9637, pin III/15, and ground.
Display: infinity ohms
5. Connect voltmeter to special tool 9637, pin III/15, and ground.
Ignition on.
Display: 0 V
If the measured values are not achieved, check wiring harness for chafing and pinching damage.
3 Perform adaptation.
1. Switch on the ignition.
2. Wait one minute.
Do not press the accelerator.
3. Switch off the ignition for at least 10 seconds.
4. Read out the fault memory.
DME 7.8
P1242
155 Fuel Injector, Cylinder 5 - Open Circuit
Diagnosis conditions
- Engine running
- Battery positive voltage greater than 7 V
Possible fault cause
- Fuel injector (coil) open circuit
- Open circuit in wiring
- DME control module
Affected terminals
Terminal III/2
NOTE: Open circuit causes the fuel injector to be continually closed.
Diagnosis/troubleshooting