Headlight Dipped and Main Beam Problems

[goodcoffeecode]

Hi all,

My K Series CSR has developed a lighting problem recently. First up, I've changed both 15A fuses for Main Beam and Dip Beam, but that had no effect.

Symptoms

• Position 1 on the 3-way light switch, no lights are on - as expected.
• Position 2 on the 3-way light switch, the side lights are on - as expected.
• Position 3 on the 3-way light switch, only the side lights are on - not expected. I would expect the Dipped Beam to be on.
• Keeping Position 3 and toggling the Main Beam 2-way switch does nothing.
• However, using the Main Beam "flasher" successfully flashes both Main Beams.

So, for some reason, the Dipped and Main Beams aren't working as expected on either headlamps. I do notice a "click" coming from within or near the fuse box when the main light switch is toggled between P2 and P3.

Anyone seen this before who could point me in the right direction please?

Many thanks,

Chris

[Jonathan Kay]

Did they used to operate normally? Any recent work nearby?

...

Do you have a multimeter and a wiring diagram? If you'd like the latter please send me a Private Message with your email address and details of the Seven.

...

Amended following #17 below.

1. Inspect the wiring and connection on the headlamp terminal of the three way switch... is it connected?
2. Check voltage on the output terminals as the switch positions are selected.
3. If 1 and 2 seem OK check that the light relay(s) is well seated and doesn't appear cooked or bulgy and that the terminals aren't damaged. Then swap it for another and test the headlamps.
4. Inspect the wiring and connection on all of the terminals on the main/dip switch... are they connected?
5. Then the voltage at the input terminal.
6. Then the same on each of the two output terminals as the switch positions are selected.

...

Happy New Year

Jonathan

[John Vine]

My K Series CSR...

I'm confused.  A K Series CSR would be a rare beastie indeed.  Could you clarify the model, year and engine?

(I suspect JK's advice will be relevant either way!) 

JV

[SM25T]

Follow the 12V to main light switch, then dip/main switch, then to connectors in lamps. Maybe both the dip filaments have failed?

[goodcoffeecode]

Hi John,

Certainly :).

It started life in 1997 as a Roadsport but was then upgraded to a Supersport R by Caterham about a year later. It has the R300 ECU, 1.8 K Series engine, 6 speed box, and the Apollo rocket thing. The Firecracker Yellow paint is wonderful :). Are these really that rare?

[goodcoffeecode]

Hi Jonathan,

Thanks for the detailed reply. I do have a multimeter, but not sure what to connect where. More info greatly appreciated .

I bought the car at the start of summer and the lights worked as expected. Not sure when they started misbehaving as I've only really be doing day driving. I have a pair of Philips H4 X-Treme Vision bulbs that I'd planned on using to upgrade the lights. However, I've not tried fitting them yet as it seemed unlikely that both bulbs would fail at the same time. I'll give them a go though. Is there a trick to getting the front off the headlight housing so I can access the main bulb?

[Jonathan Kay]

Engine off, ignition off, but battery connected.

For each of the voltage tests you need to select a suitable DC voltage range, something like 0 to 25 V. Add a photo of the meter if you can't see how to do that.

Then put one of the meter probes on a good earth, and the other on the terminal or wire that you are testing. The display should read something like 12 V wherever you want power. 

Practise on the battery terminals to see that display as you touch the probes on.

Jonathan

[SM25T]

If that is your photo, you have opened it ok. Remove plug and slide rubber boot off. Then unclip H4 bulb

[John Vine]

Are these really that rare?

Thanks for the info.  No, a K Supersport-R isn't especially rare, but you said it was a CSR -- hence my confusion.

Indeed, I had one myself, except in red:

I suspect your problem lies somewhere downstream of the lights relay, as the click you hear suggests the relay is operating.  As others have said, check for 12v at various points along the circuit, and especially around the dip/main toggle switch.

JV

 

[goodcoffeecode]

Hi John,

Now I'm confused . I though CSR stood for Caterham Supersport R? Mine even has it in the number plate (from previous owner).

[Jonathan Kay]

Can you confirm that the failure occurred before you started taking the headlamps apart?

Thanks

Jonathan

PS: I wouldn't change the lamps until I knew that everything was working.

[John Vine]

A CSR used to be at the top of the CC (UK) range:

An example.

They came with a different chassis, independent rear suspension, a 2.3 Duratec engine and a hefty price tag.  Considered by some as the ultimate 7.

If it helps, I used to refer to my Supersport-R as an "SS-R".

JV

[John Vine]

I forgot to ask...

Do you have a Handbook for your car?  If not, just send me a Private Message with your email address and I'll send you a PDF.

JV

[goodcoffeecode]

Hi Jonathan,

Yes, only took the lamps apart this afternoon. Noticed the problem with the lights earlier in the week.

[Jonathan Kay]

Thanks

Jonathan

[John Vine]

Re #13, YHM.

JV

[bjw]

Here's a diagram of the headlight wiring:-

Note that the  flasher switch bypasses the relay and dip switch so will still work with faults present in the primary path.

The main lighting rocker switch energises the headlamp relay, which in turn feeds unfused +12v to the dip/main switch. As you're able to hear the relay operate, the main switch is almost certainly o.k. and the fault lies somewhere in the path from +12v through the relay contacts and the dip switch.

Possible faults include:-

1. Relay not making good contact in its socket because the terminals have been pushed out of position in the plastic base.
2. Relay contacts burnt out.
3. Dip switch failed internally or loose connections (- even with all wires disconnected the flash will still work...)

Cheers

[goodcoffeecode]

Excellent, thanks @bjw. Can you tell me where the relay is and what it looks like please? Just had a thought... is there a bank of them behind the fuses? If so, do I just pull individual ones out and check for corrosion?

I also replaced one of the H4 bulb, but that didn't change anything.

Here's some data from multimeter readings I took at various pins using various switch positions. P1, P2 and P3 relate to the 3 positions of the main light switch. I'm not sure what to infer from it, but hopefully it'll give someone some ideas.

Component	pin	p1	p2	p3	flash
Main Light Switch	Top	0	0.03	12.51
Main Light Switch	Middle	12.82	12.54	12.54
Main Light Switch	Bottom	0	12.22	12.22
Dip Switch	Top	0	0.02	0.02	11.3
Dip Switch	Middle	0	0.02	0.02	0.31
Dip Switch	Bottom	0	0.02	0.02	0.31
Passenger Headlight	Top	0	0.02	0.02	0.31
Passenger Headlight	Nearest Car	0	0.02	0.02	11.54
Passenger Headlight	Nearest Wheel	0	0.02	0.02	0.06

Some assumptions I've drawn from this are:

• Top pin on main switch is for Head Light
• Middle pin on main switch is power from battery
• Bottom pin on main switch is Side Light
• Pin nearest car on passenger headlight is for Main Beam

[Jonathan Kay]

Well done.

That looks as if there's no feed to the main/dip switch.

Assuming that you had a good look at the connection to that switch now check the relay as above. Layout is probably:

Jonathan

 

[goodcoffeecode]

Thanks Jonathan. What do I do with the relay? Just pull it out and wipe it?

[SM25T]

Make sure they are all pushed home ... they do work loose.

[Jonathan Kay]

See if it's well seated before you pull it (crossed with Ian's). Then pull it out and have a good look at the body and the terminals. And the exposed base into which it was plugged.

If one of the other relays is identical you can swap that in.

Jonathan

[goodcoffeecode]

OK, found the relay. Removed it - it looked fine. Gave it a rub with a cloth then pushed it firmly back in. Made sure the other relays were also sat firmly. No change, I'm afraid.

[Jonathan Kay]

Crossed post.

Jonathan

[goodcoffeecode]

Good idea Jonathan. I'll check and swap in the morning.