Ford Focus speed sensor info

Dannyboytdi

I have a confusing situation with my speedometer and odometer on my ford focus. any help asap is much appreciated.

The car is a mk1 1999 ford focus hatchback 1.4 engine. I bought it 2 weeks ago. the speedometer and odometer aren't working. Sometimes the car will cut out when ive my foot on the clutch and the idle revs can be very low at times, almost cutting out.

First thing I did was get a 2nd hand speed sensor and that didn't work. Next thing I tried was getting a 2nd hand clocks/cluster and that didn't work so I brought the car to a friend who is a mechanic and he plugged his small handheld computer into it and straight away it showed the code and the fault been speed sensor. So I guessed the 2nd hand sensor I got was faulty.

I went and got a brand new speed sensor and the friend mechanic put it in and it still made no difference so he took the clock out and checked everything and there was no problem with the clocks.

The friend mechanic is puzzled and so am I.
All fuses are checked, the connector to the speed sensor has power coming to it.

There is one thing missing, the steel pin that holds the sensor in the gearbox is not there anymore. there was never a pin in it since we started working on it but the sensor is still tightly secured into position but does that pin act as some kind of Earth also??? or is it just a secure pin.

if that pin has no other purpose than to secure the sensor then it must be wiring?????? Then im thinking how can it be wiring if there is power getting to the connector.
could the wire be snapped closer to the clocks and still be power at the opposite end at the connector.

A lot of money that I don't really have has been spent so far so if anybody has come across this before please let me know. Thanks,
Danny

martinr5232

Its either a wiring problem or a ecu problem if the clocks you got are good.

Did you try testing your own cluster by holding the trip button and turning on the ignition if the needles do a full sweep they are ok.

Dannyboytdi

Yeah I tried that and all the needles are moving so clocks are good. Prob next is an expensive auto electrician?

Hal1

Get a new mechanic and try changing the coil pack.

martinr5232

Where are you someone here might be able to help you out.

dieselbug

This is a 3 wire sensor

No 1 Black/ orange should be ground, earth

No 2 white/ blue is the signal wire and sends a signal to the ecu when the car is moving.

No 3 green/ red is the 12v supply which you have confirmed is present.

You should have 12volts between pin 1 and pin 3 with ignition on.

The signal on pin 2 can be checked by jacking the wheel off the ground and spinning it. You will need a good multimeter or better, a scope to see if the voltage is changeing.

Dont rule out the possibility of a mechanical problem where the sensor is not being driven in the first place.

Outkast_IRE

I have the same car as you, with the same low idle, almost cutting out etc.

Over time it has developed to a small misfire which occurs at idle only. A compression test has shown that the compression is low in one of the cylinders, so it would be a lift the head off job.

I have decided it is too much money to fix on the age of car and thinking of just scrapping it.

The coil pack, spark plugs etc have all been changed and are working correctly.