Speedo

[Alun450]

My speedo jumps to zero when I use the windows? Any ideas. My layman idea is there off the same feed and the windows wack the current thus dropping the power to speedo? enough of my duff ideas. An expert view would help. Thanks In advance.

[MADMAX2]

take the windows out

[Bassfiend229hp]

MADMAX2 said:

take the windows out

Not sure why you would even need to use the windows when the roof is off?

[Sardonicus]

I reckon a poor earth, dont leave it track it down or you could end with bigger problems.

[spend]

The only commonality electrically is that the loom for the speedo sensor runs under the switches. Sounds like a mechanical (movement) or frayed cables shorting in that area to me. Speedo sensor is powered off the dash ignition circuit and grounded as all the other dials, any electrical problems with grounds etc would affect all the other dials pretty much the same.

Try pressing the switch body down (not operating the window) and see if you can recreate the problem, should tell you if its mechanical pressure, otherwise look for a short under the switch around the gearstick area?

[QBee]

I go with Spend, but Sardonicus could also be correct. But I am an amateur, these guys are pros.

When I had mice in the car, I had a good look at that area of wiring, and Spend is correct, the wiring to those two does pass close together.

Alun, it's not difficult to take the centre section off. Screws are at the front corners and under the triangle at the back. Speedo wires go along the top of the transmission tunnel and then through the body down to the diff right under the triangle. Window switch wires are obvious.

If you are not confident you can bring it over to mine tomorrow if you like.

[spend]

... unless some bright spark wired the modified Steve Heath sensor (in-correctly) into the window circuit ~ in which case it is probably working as the PO designed (rather than intended) it to

[Alun450]

Thanks chaps, Im sure it's done it since ive had the car, next wk QBee you can show me where to look.

[QBee]

Alun450 said:

Thanks chaps, Im sure it's done it since ive had the car, next wk QBee you can show me where to look.

Trilby a pleasure.......as the mad hatter might have said

[Alun450]

Mad as a march Hare! Lol.
Let me get this right, I've signed up for a day on a race track in a car that is about as safe as a kamikaze pilot!
On top of that it has a reputation for being evil in the wet. I've heard about putting yourself in the lions mouth!

[seeby]

Only let your windows down when stationary,then you wont notice it .

[Alun450]

Ha ha Seeby quite right, in fact below 20 mph the speedo doesn't read a thing? Looks like I've just got a new dash so will investigate when changing it over.

[jojackson4]

Alun450 said:

Ha ha Seeby quite right, in fact below 20 mph the speedo doesn't read a thing? Looks like I've just got a new dash so will investigate when changing it over.

O dear your going down my road it's not nice

[Alun450]

Jo that don't sound good!

[QBee]

Alun450 said:

Ha ha Seeby quite right, in fact below 20 mph the speedo doesn't read a thing?

Mine does that too.....

[Dr Mike Oxgreen]

Alun450 said:

below 20 mph the speedo doesn't read a thing

+1 here too. It's a very common fault.

[jojackson4]

jojackson4 said:

Alun450 said:

Ha ha Seeby quite right, in fact below 20 mph the speedo doesn't read a thing? Looks like I've just got a new dash so will investigate when changing it over.

O dear your going down my road it's not nice

I will let you know when I get to the bottom of it
Back on the stands tonight
So glad it's back to freezing just to macke the job a little more annoying
It's grim up north

[QBee]

jojackson4 said:

It's grim up north

It's bloody freezing in E Stanglia (as the weather forecasters call my part of the country) too. Monkeys are definitely brass this morning.