Real T4 problems. Useful answers.
Structured fixes distilled from solved problems, technical information and community experience. Search the symptom, narrow it to your engine, then work through the checks in order.
Fixes
1 resultStarter cranks but engine will not fire and dash lights drop out
Engines: General T4 · Years: 1990 to 2003
Symptom
The starter turns the engine normally but it will not start. A strong clue is that dashboard warning lamps which were on with the ignition disappear while the key is held in the start position.
First checks
Watch the instrument warning lamps during cranking. Check ignition-switch terminal 15 supply while the key is held in the start position. For a no-crank fault also check terminal 50, battery connections and starter wiring before condemning the switch.
Likely / confirmed cause
A worn ignition/starter switch can lose the ignition supply at terminal 15 during cranking even though the starter itself still operates.
Confirmed fix
If voltage testing confirms the ignition/starter switch is dropping the required supply during cranking, replace the faulty switch and recheck starting and accessory operation.
Useful parts / references
Ignition/starter switch (ZAS). Verify terminal 15 and terminal 50 behaviour before replacement.
Parts Library: ignition switch 6N0905865. Confirm the fault before replacement.
Parts for this fix
The Fix Database is a troubleshooting aid, not a substitute for inspection or professional diagnosis. Vehicle condition and previous modifications can change what is safe or appropriate.