Ignition Coil: Testing and Inspection

Ignition Coil N152, Checking

The following procedure is used to diagnose Ignition Coil N152.

Special tools and workshop equipment required:
- Multimeter
- Diode test lamp
- Wiring diagram

Test requirements:
- The Ignition Coil - N152- fuse OK.
- The Fuel Pump (FP) Relay -J17- OK. 4.2 Voltage Supply, Checking
- The Engine Speed (RPM) Sensor -G28- OK, 2.7 Engine Speed Sensor G28, Checking.
- The Camshaft Position (CMP) Sensor -G40- OK, 1.4 Camshaft Position Sensor G40, Checking.
- Battery voltage at least 12.5 volts
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position P or N
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.

Test procedure:
- Perform a Preliminary Check to verify the customers complaint. Refer to 3.1 Preliminary Check.

Start diagnosis:
- Remove the engine cover with air filter.
- Remove the Ignition Coil -N152- electrical connector.







Checking voltage supply:
- Switch the ignition on.
- Using a Multimeter, check the Ignition Coil electrical harness connector terminals 2 to 4 for voltage.







Specified value: battery voltage.
- Switch the ignition off.

If the specified value was not obtained:
- Check Ignition Coil electrical harness connector terminal 2 to the Fuse (on fuse panel) -29- for an open circuit.
Specified value: 1.5 Ohms Max.

If the specified value was not obtained:
- Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).
- Check the wiring connection for damage, corrosion, loose or broken terminals.
- If necessary, repair the faulty wiring connection.

If the specified values were obtained:






- Disable the power supply to the Fuel Injectors -N30, N31, N32, N33,- by removing Fuse 29 (on fuse panel B) from the fuse holder SB29, in the E-box, plenum chamber.
- Using a diode test lamp , check the Ignition Coil electrical harness connector terminals 1 to 4 and 3 to 4 for voltage.






- Operate the starter.
The LED should flicker.

- Switch the ignition off.

If the LED flickers and the voltage was OK:
- Replace the faulty Ignition Coil -N152- . Refer to Engine Mechanical, Fuel Injection and Ignition; Rep. Gr. 28 ; Ignition.

If the LED does not flicker:
Checking wiring:
If the manufacturers test box is being used. Perform the following step.
- Install the Adapter F/VAG1598 (68 Pin) -VAG1598/22-. Refer to Engine Mechanical, Fuel Injection & Ignition, Repair Group 24.

If the manufacturer's test box is not being used. Perform the following step:
- Remove the Motronic Engine Control Module (ECM) -J220-. Refer to the Repair Manual.
- Using a Multimeter , Check the Ignition Coil electrical harness connector to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 for an open circuit.











Specified value: 1.5 O Max.

If the specified value was not obtained:
- Gheck the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).
- Check the wiring connection for damage, corrosion, loose or broken terminals.
- If necessary, repair the faulty wiring connection.
- Re-enable the power supply to the Fuel Injectors -N30, N31, N32, N33- by reinstalling Fuse 29 (on fuse panel B) from the fuse holder SB29, in the E-box, plenum chamber.

- Re-connect the Ignition Coil -N152- electrical harness connector to the Ignition Coil -N152-.






- Install the engine cover with air filter .
- Erase the DTC memory. Refer to 2.6 Diagnostic Mode 04 - Erase DTC Memory.
- Perform a road test to verify repair.

If the DTC does not return:
- Repair complete, Generate readiness code. Refer to 4 Readiness Code.

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:
- Replace the Motronic Engine Control Module (ECM) -J220- . Refer to the Repair Manual.
- Assembly is performed in the reverse of the removal.

Final Procedures:
After the repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Refer to 2.4 Diagnostic Mode 03 - Read DTC Memory.
2 If necessary, erase the DTC memory. Refer to 2.6 Diagnostic Mode 04 - Erase DTC Memory.
3 If the DTC memory was erased, generate readiness code. Refer to 4 Readiness Code.

End of diagnosis.