DirtBuddha

Probably overkill for a Caterham, but I am selling my Ifor Williams CT177. Hydraulic, tilt bed, 3,500 Kgs, one owner from new and only being sold as we’re moving to a house with a smaller driveway with limited turning circle/access. It has the upgraded aluminium tread-plate centre decking, plus slide-out ramps for very low clearance vehicles. Spare wheel/tyre, wheel wrench, tool lock box and LED lights. Also comes with winch mount & bracket. It was fully serviced in June 2021 and fitted with a brand new genuine Ifor Williams hydraulic pump unit. Also comes with hitch lock key. £3,995 located near Horsham, West Sussex. Can send pictures.

No, afraid not.

I have a black S3 metric Caterham Aeroscreen that I no longer need as I've sold my car. £150 can send pics if interested.

I have a pair of S3 leather seats I'm willing to sell. will send you a BM.

Any update on this or where to get one from (as I need one too)!

PM'd you Nigel

Ok guys - I shorted the switch with a wire and YES the brake lights turn on. So indeed the switch has gone bad. I've ordered a new one from Car Builder Solutions. Many thanks for all your help - and hopefully all this info will help others in future.

Ah - ok, gotcha! I'll try doing that tomorrow and will reply.

Now that the switch looks to be prime suspect, what happens when you short the wires on each side of the switch together (with ignition on)? Do you mean like using a test light (as in the type that is a small screwdriver type thing with a probe, and a wire at the other end with a crocodile clip?) If so, I tried that before and no dice... the test light lights up when the two terminals/wires going to the brake switch get connected, but teh brake lights didnt come on...

Fixing the CC brake light switch is a 5 minute job. The spring isnt that ferocious at all, just prise end cap out gently and keep your hand over to restrain the small spring. You'll find a u-shaped contact inside ... the legs just need squeezing together a little. Clean any greasy gunk off them. I'd already tried that but to no avail...

I can't thank Jonathan Kay enough for his help in diagnosing the problem. As BC was ‘down’ this morning we communicated via email, but I have posted Jonathan's and my conversation below for future reference - in the hope that this may of help in future to people who, like me, are complete numpties when it comes to electrics! Jonathan advised using a multimeter to test the brake light switch. I was gifted a multimeter some time ago but (shamefully) I didn’t even know how to work it! Before you all laugh, I’m ok mechanically… I’ve taken engines, gearboxes, suspension, diffs and all manner of things apart and rebuilt them, I even built a Land Rover Defender 90 from scratch - every single nut and bolt - 20 years ago. But when it comes to electrics, I’m completely lost, it’s always been a black art to me. My email provider has somehow lost Jonathan’s first email, but he told me to turn the multimeter to any setting that measured voltage, put the red probe on the positive battery terminal and the black one on the negative and see if it read anything like 12v-13v. It did. Then to do the same at the brake light switch (jam a probe into each side terminal and see what it read). Morning Jonathan, I’ve done as you said and used the multimeter. On the battery it read 12.85 and at the brake light switch with the probes jammed into the terminals it reads 12.34v - very slightly lower than the reading at the battery. I’ve taken the bulbs out and they look fine. I cleaned up the Earth on the inside of each light cluster but they weren’t bad, I only did so because I hear 99% of all problems are earth related. Still no joy. -S OK… the multimeter is working and you’ve got the right range. Put the black probe on the battery negative terminal and keep it there. Then the red probe on one side of the switch: what voltage does it show? Then the red probe on the other side of the switch: what voltage does it show? And what colours are the wires on each side of the switch? The ignition needs to be ON for this test. -J Okay, with the ignition on and doing as you’ve described the multi meter reads 12.22 when the probe is on the side with the 2 wires (red wire + plain green wire) It reads nothing at all with the probe on the side with the single green wire with purple stripe. -S You now know the input and output side of the switch and that it has a live feed at the input side. Green is the ignition-switched feed, and Green/ Purple goes from the switch to the lights. I don’t know what the red wire is. With the ignition ON: Leave the black probe on the battery negative. Put the red probe on the OUTPUT side of the switch. Press the switch fully in by hand. What happens to the voltage at the OUTPUT side of the switch? And while you’re doing that see if the brake lights are coming on when you press the switch fully in by hand. -J Jonathan, you really are teaching a man how to fish rather than giving him a fish. This is hugely appreciated! So, doing what you say, with the red probe on the output side of the switch and the black probe on the battery negative terminal, when depressing the plunger on the brake switch nothing at all happens to the voltage - it just says 0.00. Also, when pressing the switch nothing happens at the lights. -S That’s the idea! Sounds as if the switch is bust. To confirm that now switch the multimeter to a resistance range, one in the section with an Ω. Touch the two probes together and it will show the low resistance and continuity. Then do the same on any piece of bare metal so that you’re familiar with the response. Disconnect all the wires from the switch Check that you get continuity when you put both probes on the same side of the switch terminal Now put one probe on one of the switch terminals and one on the other. On a working switch there’ll be no continuity until you press the switch in and then there will be… what happens on yours? -J So when I do that the multimeter shows the number 1 when the probes aren’t connected to anything. When I touch the ends of the probes together the numbers change rapidly and then settle to 001. Is that correct? I am a complete moron and I don’t know what continuity is, but when I do as you say and put both probes on one terminal on one side of the brake light switch the same thing happens, i.e. the numbers fluctuate and then settle down to 001. This is the same for both terminals i.e. on each side of the brake light switch. Re your last paragraph, when I put a probe on each terminal on the switch the multimeter reads the number 1 and when I press the plunger on the switch it stays the same, nothing happens, it still reads the number 1. -S You’re doing it right. That 1 means high resistance/ open circuit/ no continuity. That .001 means low resistance/ good continuity. Nothing happening to continuity when the switch is pressed in confirms that the switch isn’t working. Please see next email. -J It’s common for these switches to fail. A better model is available: https://www.lotus7.club/forum/techtalk/brake-light-switch-14 But it might be mendable. You can take them apart and have a look, but BEWARE… there is a little spring that makes a bid for freedom when you open the switch, so this needs to be done deep in a box. Same thread as above: https://www.lotus7.club/forum/techtalk/brake-light-switch-14 -J

@Jonathan Kay - your mailbox is full so cant reply to your msg.

I've just been out to check all the fuses in the panel (removing them 1 by 1) - all are ok. I've removed the boot floor, disconnected the multiplugs for each rear light cluster, visually checked for anything burnt/corroded (all ok), then sprayed a little WD40 into each side and reattached. Still nothing.... I'll check the bulbs and clutch split pin in the morning light, and will double-check the subloom for the Lifeline high-level rain light.

Really appreciate your help Jonathan! The brake lights weren't working when I got the car 4 months ago, so I checked all the fuses in the fuse panel (all ok), removed the boot floor, cleaned up all the connections, removed the light lenses and bulbs, made sure they were all clean etc and they started working. Since then, I had the LED Lifeline high-level rain light wired in (by a Caterham specialist) to the brake lights while the car was in for a service, in order to turn it into a high-level LED brake light. The brake lights have worked fine since then, but stopped working sometime this week (I don't know exactly when, as I just noticed them last night). I don't have a wiring diagram for my car but would appreciate one. Mine is a 2015 ex Academy car (Ti-VCT Sigma).

I'll check the fuse next then. I do have a multimeter, which someone gifted me a few years ago - but I don't know how to use it(!). I am absolutely HOPELESS when it comes to electrics. I can just about manage a test light.

Resurrecting an older thread... my brake lights have stopped working, 2 weeks after the MOT :-( I have taken out the switch, disassembled and cleaned it per the steps above but still no worky. I then put a test light (one of those screwdriver/probe type things with a small crocodile clip at one end and a probe at the other) connecting the 2 wires and it lights up. However the brake lights don't come on when the test light/probe is connected - whether the pedal is depressed or not. Would you expect the brake lights to come on when the 2 wires are connected with a probe and the brake pedal depressed (or not)?

I may sell my Caterham 7 as I'm thinking of upgrading... 2015 Caterham 7 Academy (plus) spec car with 7,900 miles. Quaife LSD (brand new), decat (will also include original Cat for buyer), full FIA cage, 6 point + 4 point harnesses, Tillett seats, lowered floors (both sides), Bilstein adjustable coilovers, AP Racing calipers, FIA electrical cutout, FIA plumbed in extinguisher, and much more. It’s had a full geo setup incl. corner weighting (flat floored) 3 weeks ago. At the same time it had a full service with new plugs, all the fluids were changed incl gearbox & diff oils, brake fluid & bleed, full spanner check etc, £2.5k just spent. ⁠ Comes with full weather equipment (hood, doors, etc) and heated screen. Fully road legal/registered and brand new MOT. ⁠ £18.25k located near Horsham, West Sussex. I can send a load more pictures if youre interested...

Don't suppose SV seats fit in a non-SV do they (2015, S3, metric car)?

Wanted - Aeroscreen and a pair of Half Doors/Side Screens for S3 (ex Academy car). Pls PM me with what you may have.