Hey guys,
Currently doing a conversion on a 95 xj6 Sovereign. I have an electrical question for the brains trust.
Do the various control modules all operate independently of one another? i.e. the engine control module and abs module.

 

No , there is one wire ( orange ) that is the digital data bus passing and cross talking to each other

This can be seen on page 234 of the 96 wiring guide as the 96 guide is more refined

This is what your OBD 2 reader is deciphering

www.jagrepair.com/images/AutoRepairPhotos/jagxj1996.pdf

 

Thanks Mate,
I'm installing a stand alone ecu and was concerned it would have an impact on the ABS etc.

 

The engine ECU mostly effects the transmission ECU

The engine ECU sends a enable to the body processor module for starter.

 

Is it a 5v signal or 12? can I bypass this feature? The transmission module will be redundant as well.

 

Which engine size ( 3.2 or 4.0 ) as that determines the starting diagram

This is the 4.0 with the more common ZF4HP24 transmission.

You will notice the Liggt Green / Black wire that is digital and this is other then the main Orange serial data bus wire

 

I really appreciate all your help. This has cleared up a great deal. What other functions does the body processor module control other than starter lockout/immobilization? Does it also handle abs or is this a separate module?

 

The ABS does still have the Orange serial data bus running through it

But the way it functions in the traction control is to mechanically retard the throttle cable through a separately wired actuator

The anti-skid using the same wheel speed sensors has no need to communicate with the engine ECU

The left rear wheel speed sensor passes through the ABS module on the way to the variable steering throw reducing for higher speeds

The speedometer are wired out side of the Orange wire , I would have to double check

 

So the orange serial data bus runs in series through all the modules? So if a module is removed I nee to work around a connection on the orange?

 

Yes and maybe it only contains the information you would extract as a code reader , the higher up devices picking up T series codes - transmission

there is another series picking up anti - skid I think is a C series for rest of chassis

One device has to generate the virgin signal as a multiplex system and the other devices modify the signal with their contributions.

 

bypass the starter relay and you don’t need the bpm to do anything 🤷‍♂️

 

Yes in the end of what the BPM provides is a ground to close the starter solenoid relay , you can obtain a ground path through the just ignition switch from pin X to 5 which is originally the ground path commanding the BPM to provide the starter solenoid relay to close with it's BPM provided ground path