saving for a timing
Join Date: Dec 2010
Location: United Kingdom
I know that feeling! After a week's worth of cleaning all the connections and relays fitting new ariel around ignition barrel and drinking beer & cursing a lot, I was ready to give up and split her for parts! Then i remembered what any car or bike electrician will tell you - intermittent fault can only be few things - bad connection, component failure, or in most cases bad earth. The code box shares the earth with some other earth cables and connects to the intake manifold on the engine. If you standing in front of the car, then on your right side of the engine, right by the injector No4 behind the thermostat, right next to the throttle body you'll see a thick cable with a eyelet bolted to the intake manifold. Take it off, give it a good clean with wire brush, as well as the bit where it's bolted to. I've put some electrical grease on there as well to stop it corroding. Never had any problems since. Key code light always goes off - engine starts! Even with a tiny 10 year old battery that barely turns the engine over.(300 CCA when new!) Give that a try. You might have a brake in the earth cable from code box, it's the pin No4 - a black cable - check continuity with earth. If you have a manual it's on the page 55-28 page 4. The big earth on the engine is the G131a for early gtv, or G60 on later gtv - Page 55-28 page 16 or 16/1. The location is on page 55-28 page 18. As for the key code light on the dash not coming on - i've no idea. have you checked the light bulb?
Hope this helps and saves a spider from extinction !