I have checked the Electrical T.S.M. but there is no mention in there for trouble codes. However here is what I found in the Service Manual Engine 103,under the heading : "Testing electrical components of CIS-E injection system.
Basic and national versions.
A. Without trouble diagnosis by means of on-off ratio
Up to March 1986 no fault detection is integrated in CIS-E control unit.
B. With trouble diagnosis by means of on-off ratio
Starting March 1986, faulty input signals are detected by CIS-E control unit and transmitted to lambda measuring output (the round six-pole connector on the left front fender). Faults are picked up by means of lambda control tester at diagnosis socket.
Fault detection permits testing different components of CIS-E injection system by means of measuring the on-off ratio.
Fault detection of control units:
On-off ratio indication Control unit
70% with fault detection
100% without fault detection "
Sorry but it seems you are out of luck here (unless of course you have one of those lambda meters :-).
Perhaps you can post the problem here and someone maybe able to help you out.