2005 K Series Alternator - Fixed

[Hulie Biasion]

Over the weekend I had an issue with the alternator, ignition light came on whilst driving and when I stopped for petrol the car wouldn’t start. Got a bump start from a guy in the petrol station. Drove home checked the battery and only 9v across the terminals.The ignition light would not come on with engine running or not running. Ordered new alternator and fitted tonight. Ignition light comes on  with the ignition on and engine not running - all ok. Battery is being charged at 14v but the ignition light does not go out when engine is running and when rev’d. Is it a faulty alternator or is there something else to check? 2005 K Series.

[Jonathan Kay]

The first thing I'd check is that the connection from the alternator to the warning lamp is correctly connected at the alternator. That's usually a Brown/Yellow wire.

What sort of alternator is it, and do you have the terminal layout?

Is it an EU3 ECU?

Would you like a Caterham wiring diagram for the Seven?

And do you know if the warning lamp was ever changed from an incandescant lamp to an LED?

Jonathan 

[Hulie Biasion]

Jonathan,

I have checked the connection several times and ensured it is pushed fully home. If you unplug it the ignition light goes out so it is making contact.

The new alternator is the same as the one that I removed, I haven't got the part no but a Alternator for a EU3 K Series 85W. The terminal layout is 2 pins in an elongated D shaped plug.

It is a EU3  K  Series so presume the ECU is the same.

I do have a wiring diagram but it is not particularly clear so if you have a clear copy that would be great.

The ignition light is an LED inside the rev counter.

Thanks for your help

[Jonathan Kay]

Please send me a Private Message with your email address and I'll send a wiring diagram.

Jonathan

[Jonathan Kay]

It reminds me of this saga.

Jonathan

[rj]

Diagrams in the 2001 assembly guide here:

 

www.caterham.dk/Assembly_Guides

 

No need to keep it secret

 

 

[Golf Juliet Tango]

http://www.caterham.dk/Assembly_Guides

[revilla]

Much nicer, clearer wiring diagrams, redrawn in full colour with a lot of mistakes corrected here:

Engine

https://andrewrevill.co.uk/EU3EngineLoom.htm

Vehicle

https://andrewrevill.co.uk/Downloads/Wiring%20Diagram%20-%20Main%20Vehicle%20Loom%20-%20Corrected.png

 

[Jonathan Kay]

What Andrew says.

Jonathan

[Golf Juliet Tango]

In colour! Isn't that nice? Well done Andrew.

[rj]

Well done Andrew!

 

[Hulie Biasion]

Thanks for all the feedback and information.

I have come to the conclusion that the issue is one of compatibility between the Alternator and the LED in the Rev counter, this is where I will focus my attention over the next couple of evenings, I will let you know how I get on.

Thanks again Julian

[Hulie Biasion]

Thanks to everyone for the information, coloured wiring diagrams and solution.

The solution was to installed a 10w 39ohm resister in parallel with the LED in the Rev counter. The LED now works correctly, on when the ignition is on and off when the engine is running.

Thanks again

Julian

[Jonathan Kay]

Well done, and thanks for adding the solution.

The common factors with the the previous case seem to be:

1. An alternator without a separate energising circuit.
2. An LED warning light.
3. EU3 ECU and wiring.

But why? Is it the need for enough current through the warning light circuit to energise the alternator?

Jonathan