Jonathan Kay

Welcome. Would you like any documentation... Assembly Guide, wiring diagrams... ? Jonathan

Please send me a Private Message with your email address. Jonathan

"... you kindly emailed me a wiring diagram months ago. Is there a key that goes with it identifying the numbered components - I know some are obvious like the lights, but some are not. If there is one, would you be kind enough to send it to me please?" In that era there was a page in the Assembly Guide matching numbers to components. Let me know if you can't find that. Then there's the "standard" wiring colours: https://www.autoelectricsupplies.co.uk/cms/files/colour_code_for_vehicle_wiring_-_new_order_2.pdf And I think that you have Andrew's corrected diagram. Jonathan PS: It could be worse... the schematic diagrams for later cars don't show the circuits end to end!

Thanks, both. In order: Jonathan

"By the way, how does one change the battery in the fob? It is a simple job of prying the fob open along the side or is there more to it?" Yes. Does the immobiliser fob have two buttons? I have the notes on arming, disarming and resetting. (And for other types.) Jonathan

Basic approach to each circuit: Check the fuse. Turn it on. Trace the 12V feed everywhere that you can access it, with the other probe on a good earth. Check the earth by testing continuity to a good earth. If you're using the fitted bulb to test a lighting circuit NB failure could be caused by the bulb or the bulbholder. Check all of the connections between the battery, engine block, starter, alternator and ECU, including the earths. Inspect, wiggle, disconnect, clean, reconnect. Battery Check the voltage that you're getting from that jump starter: 1 Connected and at rest. 2 As you crank the engine. If this isn't high enough there's a risk that the electronics won't join in as they should. Fuel pump The immobilizer doesn't isolate the fuel pump on K engined Sevens. The inertia cut-off switch does. Expose the connections at the pump and add a photo. You can test the pump itself by disconnecting it and supplying a temporary feed and earth. Rev counter If the other instruments are working then ignore this until you know that the ECU has a good feed and earth.. Rear fog light This needs the dipped headlamps to be on. Reversing light This is an earth-switched circuit. Check the connection and wiring at the gearbox. Horn The factory horn uses an earth-switched circuit. If it's operated by a button in the wheel then suspect the "pencil" switch. ECU I think that a 30A fuse is now recommended. Jonathan Edited: Crossed post.

Have you already got a wiring diagram? I'm off being murdered at a rehearsal and will suggest a plan when I get home. Jonathan

Thanks. Those should be fine. But if you decide to come off the fusebox directly there are all-in-one piggyback fuses that are a convenient means of providing another way. Jonathan

"I think in the standard wiring colours Green is a fused switched live." It is. And Caterham generally adhered to the "standard". Here's the version that I recommend: "Commonly Used Colour Codes for British Car Wiring". Jonathan

"... via a piggy back crimp connector" Do you mean doubling at the connector, eg with a double spade connector, or are you thinking of joining into the wire? Scotchloks are not favoured in these parts... Jonathan

Do you already have an Assembly Guide and an exploded diagram? Jonathan

In case anyone ever needs the types. Jonathan

Some tips: /forum/techtalk/windscreen-rubber-scuttle /forum/techtalk/windscreen-bottom-rubber-seal Jonathan

Sounds like this problem. Jonathan

For that model the fuse and relay layout should be in that printed Assembly Guide. Please send me a Private Message with your email address if they aren't. Jonathan

There are at least two types of heater. One has plastic rivets: /forum/techtalk/heater-matrix-repair-replacement ... Apart from the heater matrix there are several connections that have been repeatedly reported as leaking. Check the surface of spigots for smoothness, and you might need new clips and rings. ... Jonathan PS: It's always worth checking that the valve is fully opened and closed by the cable action.

"... don't be tempted to cut corners" : - ) Jonathan

Would you like a wiring diagram and the fuse and relay layout? Jonathan

Recommended online suppliers: Auto Electric Supplies Polevolt ... Or you could bodge the connection. Might be easiest by releasing the pins and shorting them together. ... Jonathan

Previous threads with lots of hints and tips and tricks Jonathan

Is it still smoking? Jonathan PS: Prepare yourself for "Who has a heater?". : - )

Would you like a wiring diagram and picture of the relay layout, and do you have a multimeter? Are you familiar with earth-switched circuits? And is it a button in the steering wheel? If so I'd start by checking the "pencil" switch. Jonathan

Discussion of connection to a Stack gauge. 213 Performance, the UK agent, have been very helpful. Jonathan

I'm about to replace my battery with a new Powervamp. 1800 K with a heater. It would be very helpful to see more photos of what other have done. Thanks Jonathan

If this is about replacing incandescant bulbs with LEDs... the indicator warning light probably won't work with the factory circuit. But there's a simple fix. This might also apply to the alternator warning light. Jonathan