Back to Basics - P0500 Vehicle Speed Sensor

[BlckCat]

Ok, I've posted about elctrical woes and so on , but, lets just see if we can bring the wealth of expertise here to help my woeful lack of knowledge!!

CODE 0500 - VEHICLE SPEED SENSOR A MALFUNCTION

The speed sensor on the transmission has been replaced and the wiring to iy, tested.

I have ABS, but no tracs, speedometer and cruise, (for those who don't know, the EBTCM has already been replaced).

SO, with a code 0500, where other than the transmission speed sensor would you look, can someone point me in the right direction???

Thanks, I urgently need to resolve this.

Mick

[Marks DTM Calib]

To be honest wouldn't have looked at the transmisson speed sensor at all as this feeds the auto box ECU only.

The speedo (and numerous other devices) get thier speed signal from the ABS/TC module which in turn gets its speed info from the rear ABS sensors eitehr side of the diff.....

Was thecode read from the ABS unit?

I need to check my fault code list (in fact I need to publish it!) to determine which one it is....

[BlckCat]

I would be so so so grateful if you could narrow it down from that code, to some degree my mechanic (and 100% me) is in the dark with this car, and while I trust him completely, he really could do with some insight.

When we read the code and it said VSS 'A', he questioned the supplier and was told only one sensor and on transmission so replaced it was.

If you can provide further detail, that wil be a big leap forward,

many thanks!!

Mick

[Marks DTM Calib]

So the codes were read from the ABS/TC module and not the auto box....

It might be worth having a quick look at the rear sensors in the mean time, the are mounted on the diff rear cover and pickup off the inner lo-bro joints on the end of the drive shafts (pic below) where there is a toothed section. Given them a good look over for excess crudd, damage etc (include the toothed wheel) and check the connectors which sit in little holders above the diff.

[Marks DTM Calib]

Are you sure its 0500.....I have no codes for this....

0050 is right rear speed sensor......0550 is ECU comms.....that is assuming that the codes for europe are the same as the US

We also need to know what ECU was being read (key info as 0500 is gearbox speed sensor....and you have a TC light so cold be reading the wrong ecu....!)

[BlckCat]

Mark et al,

The code is coming straight from the OBDII...

Read's...

P0500 - Vehicle Speed Sensor A Malfunction

Does this mean the ABS sensor explanation may no longer be valid?

[BlckCat]

The toothed rotors were checked and cleaned prior to the transmission sensor being replaced just to make sure, but the connectors which seem solidly attached have not been further investigated.

[Marks DTM Calib]

I suspect the wrong codes may be being read.....the ISO setup on this unit has a number of different ECU connections (K Lines)....

You need the ABS/TC ones....or try swapping the sensors for some off a breaker...

[BlckCat]

Mark, forgive my ignorance, this is not my area at all.

So, the CEL thrown up could be misleading, and the issue could well the sensors?

When you say try grabbing some from a breaker's, do you mean the electrical connector or the whole toothed thing? Sorry to be such a pain, but I am at a total loss, and this comes with a huge THANKS for all this advice.

Mick

[Marks DTM Calib]

The sensors which you can see mounted on the rear of the diff casing are held in with a single torx bolt.......you could try simply geting a spare and systemticaly swapping them over.....

My concern is

A) What has been used to read these this fault code
B) From what device has the code been read.

Its quite feasable that the code reader used might have only read say the engine ecu, this is reporting no speed signal.....whic is understandable given the TC/ABS unit isn't ouputting one!

Its frustrating for me because I know that if the car was put onto a Tech2 with the right person driving it, you could get a correct diag within 30 mins tops.....!

[BlckCat]

Maybe I'm just confusing you with uneducated answers, I apologise.

The reading comes from plugging in to the OBD11 and reading the CEL that came up, further than I do not know.

I'll plug a sensor in and see what happens.

Is it in anyway possible that this lack of speed calculation is leading to the levelling complication too?

I'm so exasperated with this.

[Searayjba]

Not sure if this helps but I have a 1999 Cat and have the factory manuals. They indicate the speed signal for the speedo, TCS and ABS come from the VSS located on the transmission, through the ETBCM. I also got the 0500 code on my code reader. Replaced the VSS on the trany without success. Now looking at the ETBCM.
If your speedo doesn't work and you have TCS and ABS lights on I would start looking at the ETBCM.

[BlckCat]

I absolutely do appreciate the advice, all of it, but sadly, thus far, I have been through 2 refurbished EBTCM's, (the second under warranty) and a new transmission VSS.

The upshot is I no longer have an ABS light out, just TRACS and all things speed related, but the P0500 code.

No one will ever persuade me this did not stem from the fitment of a remote starter, but, I have no means of knowing that.

OK my dumb question of the day, could anything have been knocked loose, in terms of feed to the speedo, behind the dashboard, ok ok, well I did say it was dumb.

I'm trying a new rear ABS sensor on thursday to see if that changes it, but I have little faith in anything Catera right now.

Thanks again!!

[Marks DTM Calib]

The manuals you have are wrong then.....the TIS software for this vehicle clearly states that the vehicle speed signal is derived from the rear ABS/TC sensors to avoid the requirement to have to setup the speedo etc for different gearbox/diff setups....

...this is backed up by my own findings in the last few years.

The biggest probelm you seem to have with this car is a lack of knowledge from the people fixing it (i.e. the repair agents)....I am not convinced they are reading the correct fault codes.

I would not be surprised if the new rear sensor fixed the fault and was the route cause of the trouble.

[BlckCat]

Mark,

Doing exactly as you suggest, and the sensor will be replaced, well when the offending one is located by testing the new one.

One question which came to mind, if the rear ABS sensor is the cause of the problem and you are absolutely spot on about the lack of knowledge base on this particular car by my very nice local mechanic, would the ABS light not be out as well as TRACs, or is that not necessarily the case?

Thanks again for all your help!!

Mick