Ignition Coil: Testing and Inspection

Ignition coils with power output stages, checking

NOTE: Ignition coils and power output stages are one component and cannot be replaced individually.

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1527 voltage test lamp
- VAG1594 connector test kit
- Wiring diagram

Test requirements





- The respective fuses of Motronic Engine Control Module (ECM) -J220- must be OK.






- Fuses -1, 2, 3, 4 and 7- in protective housing (plenum chamber, left) must be OK:
- Battery voltage must be at least 11.5 Volts.
- All electrical consumers such as, for example, lights and rear window defroster must be switched off.
- Parking brake must be engaged or else daylight driving lights will be switched on.
- For vehicles with automatic transmission, selector lever must be in position -P-or -N-.
- If vehicle is equipped with an A/C system, it must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Engine speed (RPM) sensor must be OK
- Camshaft Position (CMP) sensors must be OK, checking Testing and Inspection
- Ignition switched off.

Test sequence





- Remove fuse 32 from fuse holder.

NOTE: By removing fuse 32, voltage supply to the fuel injectors is interrupted.

- Remove engine cover.
- Remove intake manifold side parts, item 9 and side, item 16 .
- Disconnect all 4-pin connectors from ignition coils.

NOTE: Before disconnecting harness connectors, mark allocation to component.

Checking voltage supply





- Measure supply voltage between terminals 1 + 2 and 1 + 4 of the respective connector for ignition coil using the multimeter and adapter cables.
- Switch ignition on.
Specified value: at least 11.5 V

- Switch ignition off.

If there is no voltage:






- Check wire between 4-pin connector terminal 1 and relay carrier for open circuit according to wiring diagram.
Wire resistance: max. 1.5 Ohms
- Check wires between 4-pin connector and Ground (GND) for open circuit according to wiring diagram.
Terminal 2 and Ground (GND)
Terminal 4 and Ground (GND)
Wire resistance: max. 1.5 Ohms

If there is no malfunction in voltage supply:
- Check activation.

Checking activation





- Using adapter cables, connect voltage test lamp to Terminal 3 + engine Ground (GND)of disconnected Ignition Coil 1 with Power Output Stage -N70-.
- Operate starter and test ignition signal from Engine Control Module (ECM).
LED should flicker.
- Repeat test at connectors for ignition coils cylinder 2 through 8.
- Switch ignition off.

If LED flickers and voltage supply is OK:
- Replace the respective ignition coil with power output stage, ignition coils with power output stage, removing and installing.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.
- Generate readiness code.

If LED does not flicker:
- Check wires.

Checking wiring
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test






- Check wires between test box and 4-pin connector for open circuit according to wiring diagram.
Wire resistance: max. 1.5 Ohms

NOTE:
- Cylinder bank 1 = in driving direction, right
- Cylinder bank 2 = in driving direction, left

Cylinder bank 1

Cylinder Bank 1:

Cylinder bank 2

Cylinder Bank 2:

Cylinder bank 1 and 2
- Also check wires for short circuit to each other.
Specified value: Infinity Ohms

- Erase DTC memory of Engine Control Module (ECM).
- Generate readiness code.

If there is no malfunction in wire connections:
- Replace Motronic Engine Control Module (ECM) -J220-.