Motronic 5.2 System (900 Series 2.5L)

Disconnect Ignition Coil Module (ICM) 4-pin connector. Turn ignition on. Connect test light between ignition coil module 4-pin wiring harness connector terminal No. 4 (Yellow/Gray wire) and ground. If test light does not come on, repair wiring. See appropriate wiring diagram in WIRING DIAGRAMS article. If test light comes on, power circuit is okay. See MISFIRE circuit test in WIRING DIAGRAMS article.

2) Disconnect spark plug wire from cylinder No. 1. Shift transmission into neutral. Install a test spark plug into wire. Run starter motor. If spark is present, ignition system is okay. See FUEL SYSTEM  . If spark is not present, see TESTS W/CODES - MOTRONIC 4.1L & 5.2L SYSTEM article.