Desperate need of help for my Calibra speedo issues

[extraction]

Hi everyone,

I have posted this on another forum but I would like to try and get the most attention to try and get a response.

I am desperate to try and get this issue resolved but I have no idea what to check so any help would be greatly appreciated.

My calibra (95 turbo) was in a front on collision which did damage to bonnet / radiator / intercooler no structural or engine damage. I have fixed everything up and the car runs fine however I am having one major issue that is stopping me from getting the car on the road again. The speedo doesn't seem to be getting a speed signal as the speed sits at 0 and doesn't change at all. Everything else works through indicator lights, revs warning light etc. I have pulled it out the dash checked the cables etc put it back in.

Checked all the fuses and they all seem fine. I know it is an electronic speedo (not cable) from what I can gather, i am not sure if this is 100% correct, is that it gets the speed signal from the ABS computer. What I can find is what wire the signal is sent from and if there is any trouble shooting or testing I can do to try and isolate the issue. I am happy to replace parts if needed but I dint want to unless I can confirm that the part is actually the cause.

The car has been off the road for some time and I really would like to fix this so I can get it on the road again. So if anyone has any ideas, wiring diagrams of speedo signal, I would be very grateful.

[Dom]

NSF hub sensor normally drives the ABS for the speed pulse. The standard wire from an ABS unit to the speeedometer is the blue wire with red trace.

I can't help you much more than that though - if your ABS is fully working and the light goes on with the ignition and goes out when started then I suspect there may be a break in the wire between the ABS ecu and the speedo.

[Dom]

....... unless you have a gearbox with the sender bolted on where the mechanical cable would usually sit - worth double checking.

[ccm640]

when you took the clocks out is it an electronic or cable driven speedo?

[Andy K]

Put the fuel computer into average speed mode.

Drive along and press the reset button (raised button for 3 seconds or so).

Does the FC display your speed or stay on -- ?

Is the 4x4 standard and working ok without the dash light coming on ?

[extraction]

Put the fuel computer into average speed mode.

Drive along and press the reset button (raised button for 3 seconds or so).

Does the FC display your speed or stay on -- ?

Is the 4x4 standard and working ok without the dash light coming on ?

Never thought of that I will give it a try next time I go up to the garage. - do you know how this reading is determined, is it from the same sensor that gives the speedo its signal?

As with the 4x4 light well I have only driven it a small amount but it seems to come on after a few mins of driving so I suspect its not getting its signal.

[extraction]

Hi Dom,

Thanks for this information I will check this cable to see if it has a break. I dont know if it is a gearbox sensor, I have looked on the gearbox and found a couple of different sensors, removed them cleaned them and re connected with no difference. The problem is I dont know which sensor is for what. When looking on the forums people seemed to have the consenses that the new speedos get their signal from the abs and not the gearbox anymore, so I stopped looking at the gearbox.

[Andy K]

Yes the FC and speedo use the same sensor and wire.

I assume the ABS light remains off even with driving.

[extraction]

NSF hub sensor normally drives the ABS for the speed pulse. The standard wire from an ABS unit to the speeedometer is the blue wire with red trace.

I can't help you much more than that though - if your ABS is fully working and the light goes on with the ignition and goes out when started then I suspect there may be a break in the wire between the ABS ecu and the speedo.

Just another question, do you know which wheel the NSF hub sensor is on? it seems like there is at least abs sensors on each wheel so wasnt quite sure how it sent that info to the ABS computer.

[Andy K]

Near Side Front.

i.e Passenger front. (you drive on the right over there don't you)

If the ABS light isn't coming on with driving then the sensor is ok.
And as you say, it could be a simple wire problem between the ABS unit and the interior

[extraction]

Yeah the ABS light doesnt come on. I will check the FC to see if it works or not that will atleast help me determine if it is getting a signal or not.

[Andy K]

Yeap that's the next step

[extraction]

I tested the trip computer and it is not getting a reading either. I am thinking regarding the ABS light I only really drive the car 100 metres or so as its not meant to be on the road so not sure if that is long enough for the ABS to recognise a fault.

I am going to replace the ABS sensors on the front wheels to see if that makes a difference. In the mean time do you know where / which wire comes out of the ABS computer into the dash? All I can really see is a couple of wires going into it and a large plug with about 30 pins, but not sure which if any of those pins has the signal for the speedo.

[Andy K]

I'll look it up later. But it will be a blue/red wire on the large connector. One on its own without shielding. (as there will be 2 blue/reds)

[Andy K]

I think it is connected to ABS pin 17 or 19
Humm I think it maybe a blue wire on its own.

Other wheel speeds are 7 & 22

[extraction]

Hi Andy,

Thanks for that info I found this:

Fitting an Electronic Speedo from a V6

Which says pin 19, is there any way I can test with a multimeter if it is sending out a signal?

[Andy K]

As you say you need to buzz out the wire between the ABS unit and the car.

If the output is faulty (and your sure the wheel sensor is ok), you could use one of the other pins I mentioned.

Bit of a catch 22 if you can't drive it far though. Maybe you need to temporarly try one of the other pins somehow.