The can wires aren't really used for diagnostics in MK4's. They're more or less the on-board "internet" of sorts for the ECU to talk to the cluster, ABS controller, trans controller, etc. So long as you have the K-line running to the diagnostic port it should work fine. Though, without the cluster you will have a code for data bus something or other. Basically a code because the cluster isn't there and possibly another for the missing ABS and airbag controllers. Your check engine light will not work since it runs off of the can-bus system and neither will the glow plug light unless you get creative.
Topic: ALH engine and ECU management in 1998 Jetta (Read 8450 times)
