Hi

I have posted this on AFF forum before haven't gotten sorted yet
My Speedo and tacho stopped working in my fg GS mk1 . It was after I done a parasitic test for battery drain and removed the aftermarket alarm that was in the car.
When I use the obd dongle I can read both via torque pro. The cruise  control still works  and when the fuel DTE comes on on the cluster it suddenly starts counting from 80km down really quickly .

Checked the wiring for the HS Can between cluster and obd port and it's all good . Then I done a cluster sweep with isd and checked out all good (Speedo and tach swept) . I even replaced the cluster with another one and problem still persists.

All fuses checked ok 

Has anybody had this happen before and what could be the problem ?
Any help would be appreciated as it sucks not having a Speedo or tach .

Hi

 Still can not sort this issue out .

Can someone recommend an auto Electrican that specialises in canbus with Ford's in Sydney Metro area .

Have you checked all the BEM BCM connections wherever it is an a FG. This can stop the dash from working or you might need a new BEM. 

I have swapped the

BCM and the problem is still there 

Thinking might be the HIM as it has input  hs can to pcm and hs can to cluster  

 The odd thing is I can't always connect to the network (ecu) thru obd port ,says is connected to dongle but not ecu.

The other thing when I can connect with forscan it sometimes cant /

 doesn't recognise the pcm,him,abs modules  while other times it does.

I can on forscan  dashboard also pick up speed and tach via pcm but have no signal via cluster for speed and not even a gauge option for rpm via instrument cluster.

I know that the mechanical connection of the hscan is ok as the water temp , oil temp and boost works on thethey are also transmitted via hs can like the speed and rpm .

So is got me to a point where it might be EPROM issue also 

Last time I replaced the cluster and had it reprogrammed to the car the speed and rpm worked till I disconnected the battery to do some work on the car and when  reconnected th gauges weren't working again.

Recently I took It down to my tuners to get ghost cams done via pcm tech( dash not working) but the tuner could not write to the ecu and told me to check pin 13 on obd port  . When I picked up the car the speed and tach worked. I got home and checked the connection by unplugging plugs and it turns out connection from pcm to pin 13 is ok 

But when I put it all back together it stopped working again .

Not sure if it's an eeprom problem but this is past my diagnostic experience.

Did you ever get this sorted?

Yeah got it sorted after lots of head scratching and  there was 2 issues 

1st issue the ecu was not recognising the diff ratio so we reset the ecu completely and loaded newer firmware onto it .

After that was sorted we could only write to the ecu thru the obd port when we pumped more than 15v into it but could read from it at lower voltage

2nd issue -Figured out it was a bad solder joint on the can wires at the obd port where previously had an alarm wire soldered to it .

Pretty sure the 1st issue was caused by the 2nd since all this started happening when the alarm was removed.

Been good since the joint got  re  soldered