No speedo !!!!!!!!!!!! - 98 Chimaera
No speedo !!!!!!!!!!!! - 98 Chimaera
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S4CJO

Original Poster:

429 posts

289 months

Wednesday 12th April 2006
quotequote all
Just put car back on road after sorting out the brakes. Trip down to the tyre fitters for new set Toyo's, then on way back no speedo though I'm not sure it was working on the way there.

Any clues where to start

Big Al.

69,336 posts

288 months

Wednesday 12th April 2006
quotequote all
Did you leave it on the workbench, when you where sorting out the brakes?

Sorry not being very helpful am I?

paulathome

686 posts

248 months

Wednesday 12th April 2006
quotequote all
Hi there, first thing to look at is the sender unit under the car attached to the diff housing.
The sensor points at a toothed wheel which is fitted to the half shaft on the off side rear.
I have just had the same problem on my 1998 Chim 400.
Turned out to be the sensor that was faulty (they are known for being unreliable)
Jack the back of the car up and support with stands. Dive under the car and look up at the diff on the
off side. At the top of the diff (just to be irritating) is a brass threaded tube which is the sensor.
The gap between this sensor and the half shaft toothed wheel should be about 8 thou.
The sensor is adjustable by loosening the locking nut and turning the sensor with a spanner until the gap
is 8 thou, but make sure the sensor doesn't touch when you rotate the road wheel.

You may find the gap is ok but dirt between the sensor and the wheel can cause speedo problems.
If the gap is ok then it will probably be the sensor (about 40 quid from Chris Neil)

However make sure the brake lights and the reversing lights work as the speedo is powered through either
of these circuits. So if they dont work check the fuses.

Hope its just the fuses as its a bit of an arse to change the sensor as the sensor tends to weld itself to
the bracket as the bracket is ally and the sensor brass, and the exhaust is in the way just annoy you.
Hope this helps,
Cheers Paul.

S4CJO

Original Poster:

429 posts

289 months

Wednesday 12th April 2006
quotequote all
Hi Paul,

Just driven it down the road to to check my eyesight wasn't failing. Intresting that the speedo flickered into life came up to 40 then dropped down, at the same time it clocked up a few tenths on the mileage.

I'll check out the sensor and see what state that's in, car has been off the road for a couple of months while the good things in life need to happen, house maintenance. Perhaps Al had the right answer, left it on the bench or should have, done that before now.

Keep you posted.

How are things in the North West. Originally from Smallwood near Sandbach, famous for motorway closures, but now down here in the relative flat of South Lincs.

sparkythecat

8,098 posts

285 months

Wednesday 12th April 2006
quotequote all
paulathome is quite right. Odds on it's the sensor.
There's a picture of it on this thread

www.pistonheads.com/gassing/topic.asp?p=1&f=13&t=189131&h=0&hw=speedo

S4CJO

Original Poster:

429 posts

289 months

Wednesday 12th April 2006
quotequote all
Intresting reading Sparky.

Also wondered if the tyre fitters may have stuck the trolley too far under. Anyway thanks again, just off to stick my head under the back.

Cheers

paulathome

686 posts

248 months

Wednesday 12th April 2006
quotequote all
I dont think a fitter could get a jack up amongst the diff to damage the sensor.
The chassis would stop any likelyhood of that. (that includes a kwik fit fitter too)
Sounds a bit like mine though, first thing in the morning the speedo doesnt read for the first
20 mph or so then bursts into life, then after that all is ok. (sounds to me like the after effects of storage to me)
Hope you sort it.
Cheers Paul.

mrsflipflopgriff

501 posts

276 months

Wednesday 12th April 2006
quotequote all
S4,
The jumping to a speed and then dying is exactly what ours did a few miles before it died. It was the sensor.
It's a bit of a bitch to get to but an easy DIY job.
If the tyre fitter damage dthe sensor then there's likely to be a big hole in the body somewhere too!! I would have thought very little chance of that dpeending upon where the sensor connector plug is - mine was as far back on the chassis towards the rear on a down piece tucked well away - waterproof tape it up and put a placcy tie around it to secure it out the way and free from water ingress.
FFG

S4CJO

Original Poster:

429 posts

289 months

Wednesday 12th April 2006
quotequote all
Hi Paul,

Your spot on, went under and no way could the fitter even accidentally get the trolley in there I could hardly get my hand in. Have the use of a ramp at the weekend so I'll se if I can get it off or at least check the output.

Reversing lights etc all working so I anticipate the fuse is OK.


petros

2,441 posts

259 months

Wednesday 12th April 2006
quotequote all
Agree with all of that, mine did that, new sensor ( fitted by someone who knows what they're doing) been fine since

S4CJO

Original Poster:

429 posts

289 months

Wednesday 12th April 2006
quotequote all
Mrs FlipFlopGriff,

Thanks for the reply. Will check out the DIY job at the weekend, I bet the sun will shine all weekend while I'm under it's back end. Anyway rather get it working than getting points...........