VP Calais level 3 cluster speedo not working

[abs351]

****Solved**Hi, I have been handed over a problem of which many auto elects and mechanics have looked at a vp Calais 5ltr auto, of which the speedo doesn't work.
The VSS has been changed out many times. With new ones and genuine 2nd hands with no luck.
Apparently speedo worked for 30 mins, then failed and never worked again.

The cluster has been sent off for testing and passed their test with video footage of speedo moving.

The car vss wiring has been tested for continuity and power is present at the plug of vss.

So I requested a VSS, tested it on the bench and it pulses.Measured with multimeter and oscilloscope.

I requested the cluster now to bench test with the VSS which no one has done as of yet.

I have wired up the VSS with the same powe source and gnd as cluster. I took the signal wire from VSS and wired to speed signal pin on cluster.
Everything has powered up including the vdo level 3 cluster and power sources on the back of cluster. I then placed a drill on speed sensor (reverse and forward) I don't see the speedo working. I have soldered wires from cluster pinout to points to make it easy to power up on bench.
I have reviewed the schematics and it seems to be interconnected to cluster.
I also noticed the trip computer middle LCD doesn't work. Either its faulty or requires an ECU connection?
Has anyone bench tested these clusters
Or shed some intel why its not working? Have I missed a gnd or signal gnd wire?
Thanks

[pman92]

VN VP use a hall effect / square wave speed signal / sensor.

Image on your oscilloscope looks like an inductive one.

Do you have a complete photo of the speed sensor? Does it have 3 wires? Are you sure it's the correct one?

[Gareth]

Second that, that wave pattern looks incorrect

[abs351]

Thanks for the reply guys..I may not had it setup correctly in that photo.

Its a 3 wire sensor. To be sure for testing looking into the connector.

There was 2, so called heavy duty and standard.
I was given the sensors.

See attached pic.
Appreciate your help.

[Gareth]

Can't tell from your pics how you have it wired but it should be - Pink 12V, Black earth, Purple/white signal out.

[pman92]

Do they both actually have 3 wires in the plug?

Test them both on the scope and see.
The signal in your previous photo definitely looks like an inductive type.
They should be a square wave hall effect type.

You may need to add a pullup resistor to see the signal. Cluster has it built in, but if your checking the sensor by itself you may need to add one.

[abs351]

Hi thanks for the prompt reply. Yeah definitely 3 wire.
I will re check with the scope.

Looking at the connector, 12v RHS, GND LHS and bottom connector signal is how i wired it up and the colour code of the non genuine was red rhs , black lhs and blue bottom for signal also.

I was thinking it needs a pull-up resistor when testing alone the vss. I assume pull up to VCC. What size resistor 10k?

Thanks.

[abs351]

Had a quick look tonight. Used a 1k resistor as a pull up to vcc.
Square wave is present on scope .multimeter reference from 12vdc to 0v of turning of shaft on vss. So its working. I got the cluster kms to work. Wired power and signal source direct to the dial. So its all confirmed working.

How do you guys test the cluster?

. I'm going to use a 555 timer to build me a square wave generator for future projects, but for now the vss is good enough to test this cluster.

Thanks for your help