wiring help

[jlupicki]

I bought an Alpine. This was good news for the seller and mixed reviews for me. The brake lights won't come on. I have verified the pressure switch is functioning. I have also verified that there is voltage coming to the switch but only with the key on. This would mean that the brake lights would not function normally with the key off. Is this the way it's supposed to be? I have no way of knowing if this is a stock wiring harness or a home made one but my guess is that it is the latter.

Any advice is appreciated.

 

[hartmandm]

What series Alpine?

The wiring diagrams for series 1 through 4 are here (go to page 51):
http://www.sunbeamalpine.org/downloads/WSM 124 SI-SIV Manual/15 Electrical System (N).pdf

The wiring diagram for series 5 is here (go to page 18):
http://www.sunbeamalpine.org/downloads/WSM 145 SV Manual/15 Electrical System (N-2).pdf

Compare your wiring against the appropriate diagram and you should be able to tell if you have a stock wiring harness.

Do you have voltage 'leaving' the pressure switch when the ignition is on and the brakes are applied? If yes, then also check for voltage at the brake lights.

Have you verified ground connections for the brake lights?

Mike

 

[Tom H]

Mike's advice is spot on. Look at the diagram. And you will see that on SIII thru SV (not sure of the others) the brake lights are on the Green circuit, which means they are switched by the Ignition switch and are fused. The brakes lights should work if your wipers work! - Same green circuit.

Tom

 

[hartmandm]

While doing your tests, don't leave the ignition on with the car not running for very long. Other folks have said that will cook the ignition coil.

Mike

 

[jlupicki]

First let me thank you all for the good information. To give you all more information, the car is a 1967 so Series V. I have traced the wires into the car from the engine bay. There are 2 wires joined together at a wire clip that goes on the pressure switch. These are both green. These are the ones with power when the key is on. The other wire at the pressure switch is green with a purple tracer. It goes to what I think is the flasher. It is a silver cylinder with 3 connectors and is plugged into a socket with 2 other wires that are green.

The wipers do work but no brake lights. I haven't looked at the diagram yet. Will try to do it this weekend.

I am still hoping that some of this will make sense to one of you and you will know the answer. Thanks again.

 

[65beam]

help

the series 5 has two green wires connected together and also a green with purple so you have the right wiring. switch the wires around and see if it works. the brake light switch will stick if not used for a long period of time which means the lights won't work. get a big wrench and smack the switch. if it's stuck this should get it to work. I've done it many times over the years. this was a tip from tiger tom many years ago.

 

[hartmandm]

It sounds like you may have a stock wiring harness.

Definitely review the wiring diagram.

There is a green + purple wire connected to the flasher unit (3 prong metal can). However, that is a different circuit than the brake lamps.

The green wires connected to the pressure switch are hot when the ignition is on.

The green + purple wire on the pressure switch should connect to the brake lamps and go hot when the pressure switch closes.

As a test, remove the green + purple wire from the pressure switch. Turn the ignition on and apply the brakes. Do you see a voltage on the exposed connector? If not, the pressure switch is the problem, assuming the brake pedal is building pressure in the brake line.

If the pressure switch checks out, reconnect the green + purple wire at the pressure switch. Then open the trunk and locate the green + purple brake lamp wire in either space behind the tail lights. On the left side you will see two green + purple wires into a single connector. On the right side, there is a single green + purple wire. Test each side to see if the green + purple wire connector goes hot when the ignition is on and the brakes are applied.

If that all checks out, then check that the brake lamp metal housing is grounded by doing a continuity test between the lamp housing and the car chassis (e.g. the trunk latch). There is no separate ground wire for the tail housing. The ground is established by the screw threads plus wing nuts that mount the tail housing.

If the brake lamp housing ground continuity is good, then check the brake lamp bulbs.

Mike

 

[PaulK]

This is a good discussion, as I will be going through some of the same issues soon. I am connecting up all the wiring in my SV after many years of it being stored in boxes.

Thanks

 

[jlupicki]

OK. I have determined that the pressure switch needs to be replaced. Is this an item available at the local auto parts store? Is a brake bleed necessary? Thanks to all for the great help.

 

[Greggers]

Lemme save everybody the effort of the next 10 or so replies.

1. Someone will say you can try rapping the pressure switch with a hammer to get it working again.

2. Someone else will say that it's crazy to do so with a thing that could mean the difference between getting rear-ended or not.

3. The first person will say that he did it 20 years ago and it's still working.

4-5. More comments on the hammer, both supportive and condemning.

6. Someone will tell you to get one from Sunbeam Specialties.

7. Someone will tell you that if you open the brake system, you have to bleed it. Oh, and whatever was in the brake system that caused the pressure switch to clog up will still be in there, so you might as well take this opportunity to completely flush the system.

8. Someone will tell you to contact Bill Blue who makes a mechanical switch that avoids the unsafe pressure switch.

9. Someone else will say they're not sure if Bill is still making them.

10. Bill will let you know if he is.

 

[65beam]

help

don't use a hammer. you may break the switch housing. smack it with a wrench. it may take more than one smack. I first did this about 30 years ago and have continued to smack it on all of the cars from time to time. the last being shortly before the united a few weeks ago. the Harrington lights didn't work. bill sold his kits at the united and I bought one and plan on using it on the RHD Harrington some day when it gets to where I need the switch. I am going to change the mounting a little by using a bracket similar to what the fastbacks used. Chrysler did change over to the style of switch bill uses when they switched body styles in 68. I seem to remember that the 69 now has a switch from a Honda of some kind. even though I had NOS switches for it I didn't use them because the plastic housing is two piece and pops apart. the switch is also part of the brake system and if not used it will stick just like the calipers or wheel cylinders. put a bunch of rags under the switch to catch the fluid and quickly make the switch of units. that's about all it takes.

 

[hartmandm]

What Greggers said is all likely to happen. You will hear some differing opinions on what to do.

If it was me...I'd just replace the pressure switch and bleed the brake system.

I do trust Sunbeam Specialties replacement parts. In this case, I don't see the brake pressure switch listed in their catalog.

The Beck Arnley catalog lists the replacement part as 201-130, but I have not personally used that part.

You don't want to mix brake fluids. Do you know what type of brake fluid is currently in use or can you contact the previous owner to find out?

The original brake (& clutch hydraulics) fluid was Girling (DOT 4). Today you can still get the DOT 4 as Castrol LMA / Castrol GT LMA. E.g. http://www.amazon.com/gp/product/B000WPB6DS

If you end up having & sticking with DOT 4, go for the smaller bottles. Once the bottle is opened, use the fluid within a month or so. It goes bad.

And if you are using DOT 4, I recommend you "flush" the system once a year (i.e. follow the bleed process and push new brake fluid through the whole system) to eliminate any moisture build up. Given you are a new owner, this can be your first system flush.

Just one person's opinion. Good luck.

Mike

 

[jlupicki]

I have decided to go with a more modern setup. I am making my own bracket and will be using a brake light switch inside the car. I am leaving the existing pressure switch in place and will not be messing around with the bleeding the brakes.

If anyone has a spec on the inside the car brake switch from the Bill Blue kit and would like to share it that would be great.

Incidentally the hammer/wrench method didn't work at all. Interestingly the switch works per the volt/ohm meter but absolutely will not with the real wires attached.

 

[chazza]

Interestingly the switch works per the volt/ohm meter but absolutely will not with the real wires attached.

Can you clarify what you mean?

If the switch sends a continuity signal to the meter each time the pedal is depressed, then there is nothing wrong with the switch, unless it is an intermittent fault and only happens occasionally.

Do you mean that when the wires are attached, there is no brake light with ignition on and pedal depressed; or are you attaching test leads to the switch? You can use test leads with the continuity meter, or with a globe to test the switch remotely and save an aching back.

If the problem is with the brake lights, then start checking the wiring and joiners working from the switch towards the rear of the car. This is presuming that you have already done the easy bit first and checked the globes for continuity and that the lamps are properly earthed/grounded - I put separate earth cables on my lamps.

If you have a close look at the wiring diagram it shows where the harness is joined, so it is worth pulling the joiners apart and cleaning them and lubricating with WD40 or similar. You can test the cable for current at each join by inserting a test lamp and earthing it, whilst the ignition is on and the pedal depressed. If you suspect a cable is broken internally use very long test leads to connect the ends to the continuity meter. This may seem unlikely, but on my car there were three breaks in the wiring to the fuel sender!

Good luck with the search; it can be quite enjoyable finding the faults and fixing them,

Cheers Charlie

 

[Tom H]

Like Chazza I am puzzled by your statement.

A quick check of the wiring is to pull the two wires off the switch and put a paper clip or other connection between the two wires. If the brake lights don't light with the ignition sw ON, then your problem is something other than the switch.

Tom

 

[jlupicki]

A test of the switch indicated it was functioning properly. Resistance dropped to zero with brake applied. With the brake wires attached to the switch and key on, the brake lights would not light. A jumper to the wires lit the brake lights. Something isn't working with the pressure switch. I am not going to mess with it anymore and am not going to replace it. I am going with the "Bill Blue" type of mechanical switch mounted inside the car.

 

[Tom H]

good test, good plan!

Tom

 

[hartmandm]

I still recommend you find out what hydraulic fluids are in the brakes and clutch and flush both systems if DOT 4.

And note that DOT 4 brake fluid will eat paint, so use plastic and towels to catch any drips.

Mike

 

[DanR]

Good advice!

Mike, I think you have made some very good advice for pure safety sake.

DanR