Brake light switch

[jschwartz]

I've had a number of fellow motorists pull me over on the roadside to inform me my brake lights are not working. They are working, but require a bit of pedal pressure to activate the pressure switch. I've discussed with Ted and it appears this is normal. Since the car's so light not a lot of pressure is required to slow the car during normal stop/go driving. Has anyone changed to a lower pressure switch to activate the lights sooner? or a mechanical switch.
Anyone know the thread size on the pressure switch?
thanks
jeff

[BobM]

This is a common problem on '7' type cars Jeff. Apparently also sometimes it's possible to get an airlock in the switch itself. Most common solution I've heard of is to go for a microswitch triggered by the brake pedal.

[davefiddes]

The brake bias will have a significant effect as well I would have thought as the switch is just on the rear circuit.

[jschwartz]

Everything is working pretty well. Before I had the bias dialed in, they really required a lot of pedal pressure to activate. I'd like to change to a lower pressure switch if possible, the micro switch is an option. I'm just tiring of the one off modifications, I've done a load of them. And trying to get under the dash is nearly impossible.
Anyone know the thread size of the pressure switch?
Can any of you builders check yours for me?
Don't want to take apart my brake system to just to get the thread size.
thanks,
jeff

[BobM]

jschwartz said:

Anyone know the thread size of the pressure switch? Can any of you builders check yours for me?

Just took mine out and it looks like it's 3/8" UNF, I certainly don't have any (metric) nuts which will fit it and my 3/8 UNF die goes straight on easily.

>> Edited by BobM on Thursday 9th October 07:42

[shithotfast]

Over the past four years of the car on the road, I have had 3 of these switchs! The "light load" answer is not the right answer. your switch is on the way out! Mine went the same way. Replaced it, and the slightest touch and it worked. Suggest you order a couple of spares, they DO go and cant be fixed without replacement.

[jschwartz]

$75 for the shipping alone on my last small parts order. It'd be great to source it here in the states.
jeff

[BobM]

jschwartz said:

$75 for the shipping alone on my last small parts order. It'd be great to source it here in the states.

I'm sure one of us could get you one out there for less than that Jeff. If you're running into trouble finding one let me know and I'll price one over here.

[Steve_D]

Bob you beat me to it.
The switch is £7.42 plus VAT and postage so it's not a big deal.
Steve

[Chewy]

I have had the same problem in that my brake lights only ever came on under very heavy braking. I have received a new switch this morning but mine was £13.60 plus VAT direct from Ultima. I didn't think that was expensive but it's nearly double the cost you quote Steve. Have you got another source?

[Steve_D]

BGC Motorsport Part# BPS3824 £7.42 (just noticed August 2002 price list but may still be valid)

Think Automotive Part# BLS8-3 £12.45 (does not say what thread)
Steve

[bigmack]

Jeff,
I bought mine from Pegasus Auto Racing in the U.S.. They're online catalog is on the web. The switch works well and has the same thread dimensions.
Cheers!
-Mack

[andycanam]

Good to see you posting again Mack.