is, as you say, "Data exchange fault between individual control modules".

Also DTC 17 for the LH-SFI Module is "CAN data: Elec Acc Module - no data transmission". So suspect the new harness is not guite right especially if it worked ok before the harness swap.

With an ohmeter, remove the Diag Module, then check the resistance between the TWO WIDE PINS; sb 60 ohms +/- 5.

Pull out the LH-SFI (N3/1) module, then check the resistance between the TWO WIDE pins; sb 120 ohms +/- 5.

Then check that there's continuity between the corresponding pins between the two modules. Most likely one or both is not making. That's due to the wiring harness 'replacement'.

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Regards . . . . JimF
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'94 S500 Cpe

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