Ignition Coil: Testing and Inspection

Ignition coil, checking

- switch OFF ignition
- disconnect harness connector and ignition wire from ignition coil (N 152)
- switch Fluke 83 multimeter to resistance range




- connect multimeter between terminals 1 and 15
- primary resistance must be 0.5 to 0.7 Ohms

- connect multimeter between terminals 4 and 15
- secondary resistance must be 3000 to 4000 Ohms

If specified values not obtained
- disconnect ground strap from battery
- remove ignition coil and unscrew power output stage (N 157)
- repeat check


Ignition coil power output stage

Voltage supply, checking
Requirements
- no DTCs stored in DTC memory
- electrical check of Motronic system OK
- ignition coil OK

- disconnect harness connector from ignition coil power output stage
- switch Fluke 83 multimeter to 20 Volt range




- connect multimeter to terminals 1 and 3 of harness connector using adaptor leads from VW 1594 adaptor kit
- switch ON ignition
- must be approx. battery voltage

- switch OFF ignition


Power output stage triggering, checking




- connect US 1115 LED tester to terminals 2 and 3 of harness connector using test adaptor VW 1594/15 from VW 1594 adaptor kit
- operate starter to check ignition signal from engine control module
- LED tester must flicker

If NO
- replace engine control module (J 220)
- re-connect harness connector 4 and coil wire to ignition coil




- connect LED tester between terminals 1 and 15 on ignition coil using jumper leads from VW 1594 adaptor kit

CAUTION: During the following check, DO NOT touch any of the exposed terminals or connectors from the ignition coil or adaptor wires.

- switch ON ignition
- LED tester must light up for 1 to 2 seconds

- operate starter
- LED tester must flicker

If NO
- replace ignition coil power output stage