Jump to content

Hand Brake sensor


Recommended Posts

The switch is a small sliding jobbie similar to the workings of a door "pin switch", it's mounted on the handbrake lever base (mounting) plate under the rubber gaiter. there's no adjustment as such other than possibly bending the metal lever that operates it.

Generally though they seem to suffer mostly from bad connections, either internally, or the spade connector that plugs into it works loose.

They can also remain on, if something is blocking the lever and preventing it from releasing fully, the switch often comes on within the first few degrees of movement of the lever.

Link to comment
Share on other sites

The switch is a small sliding jobbie similar to the workings of a door "pin switch", it's mounted on the handbrake lever base (mounting) plate under the rubber gaiter. there's no adjustment as such other than possibly bending the metal lever that operates it.

Generally though they seem to suffer mostly from bad connections, either internally, or the spade connector that plugs into it works loose.

They can also remain on, if something is blocking the lever and preventing it from releasing fully, the switch often comes on within the first few degrees of movement of the lever.

Ah, ok, well mine is on constantly, and it never turns off, unless for some reason i go on a very long drive, and then it flickers a bit

Any thoughts?

Thanks

Link to comment
Share on other sites

  • 3 weeks later...

Did you find out what is causing your light to stay on? I am having similar problems with a D-90, and also a flickering light with a D-110. I just took the switch off on the 90, and cleaned it up, and put a ohm meter on it, and it seems to be working fine. Well, if working fine means that the switch is normally open, and when you depress the actuator plunger it closes the switch.

Anyhow, I cleaned it all up, put it back together, and verified that the switch is getting opened and closed by the hand brake lever while installed. But the light still stays on. So, it seems that shorting the wire to earth turns the hand brake indicator light off? Actually, I didn't try that. Yet.

I checked the single wire that comes from that switch, and it is not chafed or disconnected under the body. It goes through a connector and then into a wire harness. No signs of damage.

Does this make sense?

Link to comment
Share on other sites

not cheap had to replace mine last weekend, came in a MG/Rover bag.

ha, I believe it. And to an old DIY like me stranded on a desert island....EVERYthing is expensive.

BUT I digress....

You see, the switch is NOT stuck or dead. Little spring works just fine, pushes plunger in and out. When out, there is no resistance between the terminals. Plunger out, switch is closed. When the cam on the hand brake lever pushes it in, it opens the circuit. Which means that the single wire that goes to one exposed terminal....... is normally shorted to ground Or earth, as I believe you guys say, when the brake is on. Now, the funny thing is that this seems backwards, to me. I would think that pulling the brake on would close a circuit and light the lamp.

I am unclear on how this is supposed to work. It defies my limited logic and makes me want to drink.

I mean, if it were just a messed up switch, it would seem that unplugging the wire would turn the lamp off. It doesnt.

Hey, I just thought of something. I am going to go out and try shorting that wire directly to the chassis. Right now....

Link to comment
Share on other sites

with the handbrake on & ignition on, the switch is earthed out which lights the dash warning light & when the handbrake is released to move off the switch moves to the 2nd contact & puts the light out, if the light is on with the handbrake released the white/yellow wire must be earthing out somewhere along it's route to the dash warning light panel.

wire route on mine comes from the handbrake through seatbox along the chassis rail, up the bulkhead to a multiplug by the brake servo, a male bullet connector fits the multiplug & then goes throught the main loom grommet to the dash warning light.

Link to comment
Share on other sites

Ah ha! It all became clear.

First, of course, I unplugged the single wire connector from the switch on the hand brake lever assy. Stuck a small nail in that and shorted it to chassis. Light stayed on. Then I climbed underneath and wedged my poor old sunburned shaven head up between the muffler, propshaft, and floor. or ceiling, I guess it is when you are under it.

Found an inline connector there, took it apart. inspected it, as it were. No probs with that.

Then, while ruminating and remounting the two rear tires, and cursing the idiot who specified alloy wheels with those stupid ( and I do mean stupid) lug nuts that need a special tool to operate.....the light came on. Well, metaphorically and mentally speaking, of course. There must be something else on the circuit.

SO, I checked the brake fluid resovoir, which was near empty. ( I had disassembled both real caliphers to clean them up after they froze up due to sea water, negligence, and stupidity. All but the first one mine.)

And the brake fluid resovoir cap has a sensor in it. And guess what, fill the resovoir, and the brake light goes out. Assuming the hand brake stuff is all okay, of course.

SO, that was it. It's a multifunction brake indicator light. It indicates something is wrong with the brakes, somewhere. WOuld have been nice to read that in the manual two days ago. If it's there, I can't find it. It only mentions the hand brake.

Western, sounds like the wiring on your switch is different. Mine is definitely switch closed, and wire earthed, when the light is on.

Link to comment
Share on other sites

My 110 is a 1989 vehicle & I fitted the handbrake switch [see the link in my 1st reply above] on my 110 it didn't have the low fluid sender unit when bulit, but did have the warning light in the dash, so I fitted the switch/wiring & since fitted the low fluid sender as well as the factory fitted PDWA switch.

so yep a bit different from the normal 200/300Tdi Defender set up.

since you found the low fluid was causing the light to come on & fixed it, the same light also acts as a handbrake on tell tale warning when the brake hydraulics are fully functional.

Link to comment
Share on other sites

Oh, yeah I did a "search" and also looked at the photos in your link.

Does your switch have two wires? or just one?

This was driving me nuts. I even put on my highest magnification eyeglasses and was trying to see if somehow the switch was switchable, but nope. It's about as simple a switch as there is. Moving contacts and a spring, basically.

Well, now the hand brake is all freed up, and the rear caliphers cleaned up, and I was able to start it up and drive it out of the garage. Tomorrow, I will work on the front brakes.

Unless the weather is good. There is a Marlin tournament going on and I might want to go do some fishing .

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy