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Discussion Starter #1
hello, we have a ex sky with 2 ecu sockets either of which can be read, has any one came across this before (hopefully yes) and how do you get round about it if you break down??
Van remap has brought this to light so ecu has to be removed for remap to be done ok takes a little longer but if poor RAC or AA man can't talk to the van I have a problem

Cheers for any help that comes my way

Gordon
 

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I guess you mean that it has two OBD diagnostic sockets in the driver's footwell? These aren't specifcally for the ECU - the sockets are wired to a diagnostic gateway on the back of the instrument panel, and you can get diagnostic data from any of the van's control module through it.

Adding a second one is not something I have seen done before, and it's not easy to think why they would have done it. At the simplest level it could be that one was added to allow a small solar panel on the dash to charge the engine battery when the van was laid up, but that sounds unlikely (and it's not recommended by VW either). The other possibility is that they neede two sets of equipment connected up full-time, though again, it's hard to think why.

You'll probably only find out the answer by looking at the wiring on the back: are both sockets wired the same (i.e. in parallel), and is there any additional equipment wired to the back of one or both?
 

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Follow cables back it's possibly a piggy back loom for something aftermarket also you don't mention model/year with good remap kit ECU don't need to be removed so be careful who your using for your remap
 

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Discussion Starter #4
I guess you mean that it has two OBD diagnostic sockets in the driver's footwell? These aren't specifcally for the ECU - the sockets are wired to a diagnostic gateway on the back of the instrument panel, and you can get diagnostic data from any of the van's control module through it.

Adding a second one is not something I have seen done before, and it's not easy to think why they would have done it. At the simplest level it could be that one was added to allow a small solar panel on the dash to charge the engine battery when the van was laid up, but that sounds unlikely (and it's not recommended by VW either). The other possibility is that they neede two sets of equipment connected up full-time, though again, it's hard to think why.

You'll probably only find out the answer by looking at the wiring on the back: are both sockets wired the same (i.e. in parallel), and is there any additional equipment wired to the back of one or both?
 

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Discussion Starter #5
Yes sorry OBD sockets I just doesn't make sense for there to be 2 as it's a ex Sky van possibly something they had fitted into the van but how have VW done a read from it in the past as it has a full service record from VW upto when i bought it
 

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How are they wired up at the back of the sockets? Until you know that it's all just guesswork.
 

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A friend of mine recently bought an ex courier van (not a VW) which used an OBD port replicator to provide 2 OBD sockets - apparently the courier firm used a monitoring/tracking device with had to be permanently attached to the OBD port - a second port had to be provided so that the device didn't block the port in case it was required for diagnostics purposes.
 

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Discussion Starter #8
The sockets are the same wiring is a professional job all nicely wrapped up how far back got no idea until I pull off the whole lower dash/ console area
A friend of mine recently bought an ex courier van (not a VW) which used an OBD port replicator to provide 2 OBD sockets - apparently the courier firm used a monitoring/tracking device with had to be permanently attached to the OBD port - a second port had to be provided so that the device didn't block the port in case it was required for diagnostics purposes.
Same thing Sky must have fitted same sort of system put either the ports would give data signal for a comms test which is the worrying thing
 

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Only issue would be corruption on the data on the CAN bus. It should be obvious which one is the aftermarket port. Just remove it.
 

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Only issue would be corruption on the data on the CAN bus.
Why would you get corruption? It's a bus architecture - it's designed to serve multiple points, and to detect and resolve any conflicts if multiple devices try to send data at the same time.
 

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Why would you get corruption? It's a bus architecture - it's designed to serve multiple points, and to detect and resolve any conflicts if multiple devices try to send data at the same time.
CAN should be twisted pair with 120 Ohm termination at each end of the bus. It's pretty fault tolerant by design but I've seen networks pulled down by bad wiring. (Im an E&SW engineer and spent 13 years in OEMs designing the things!)
 
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