Starter issues (alarm?)

Has anyone ever see a Coupe 16v Turbo that wont turn over when trying to start, however if you turn of the the headlights, it starts just fine. I suspect the original alarm system, is has been turned of as long as i've had the car, but looking at the diagram the starter wire goes through the controlbox for the alarm. So that must be it, seems to messure the voltage at wont allow starting with low voltage. Can it be disconnected og can i just bypass the starter wire.

Sounds like a classic case of a low battery voltage and/or bad connection at the battery and/or a bad earth...

1.With headlights on and a low battery, there is less current available to drive the starter motor, to the point where the solenoid on top of the starter motor might engage (click) but as soon as the motor tries to draw the high current needed, the voltage drops and the solenoid clicks back open. The headlights will also dim when trying to start.

Solution: charge or renew the battery

2. If either or both battery terminals feel warm after trying to start, this indicates a poor connection which increases resistance to current flow. But there can also be a poor connection without the terminals feeling warm.

Solution: clean battery posts and terminal connectors, ensure tight connections

3. A bad earth connection (eg: on the engine block) can also prevent the high starter motor current from flowing.

Solution: check and clean all earth connections on engine

New battery, fully charged. No power drain when trying to start, ground cable is in fine both for the chassis and the engine.

What alarm system do you have? Factory fit (non-UK cars) or importer/dealer fit (UK cars, usually either Scorpion 918U or Meta M99)?

Factory mount. 16vt 96 non UK.