I'm trying to troubleshoot the SRS in a 1996 Discovery, but my Hawkeye diagnostic unit keeps giving me a "data link error." I'm using the Bearmach-supplied cable and a BA5077 adapter. The Hawkeye connects properly to the Disco's EMS ECU and I was able to connect to my 97 Disco's SRS - just no joy with the 96. Keep in mind the 96 has the TRW MPS SRS while the 97 has the SPS version so there's a difference there ... if the problem is in the comm protocol to the MPS unit I don't have a way to check that. I verified the Rover's SRS fuses, inspected and confirmed wiring at the OBD-II port is correct, checked wiring at the ECU by tracing connections back to the OBD-II connector and verifying power and ground. I even dis-assembled, chased, and verified the BA5077 adapter's wiring. I did find a high resistance to ground on pin 13 of the ECU connector, and cleared that by de-mating and re-mating an SRS connector under the streering wheel that happens to be in the ground path. No luck though .... that stubborn "data link error" persists.

I swapped out the ECU with another I bought on eBay, but have the same problem. I've no way to know whether the replacement was working or not though .... maybe I've got two faulty ones?

So here's where I'm at: I'm confident the vehicle wiring is good. Either the Hawkeye comm protocol is not suited to the 96 Disco Multi-Point SRS or the SRS ECU is bad. Anyone else out there run into anything like this? Or can someone with a TRW MPS equipped SRS and Hawkeye diagnostic tool run a quick check for me and confirm the tool really does talk to that particular model ECU?

 

It’s been a while and I’m hoping you solved your issue. I need to reset my ‘96 SRS light and I’m curious to know if Hawkeye will be an option or if I need to look for something else.
Nanocom keeps telling me it is not supported (eventhough the P38 with the same SRS ecu is supported!?).

 

I’m pretty sure that Nanocom only does P38 and Disco 2 (and newer). You should post your technical questions in the Disco 1 section of this forum. You’ll get a lot more traffic there.