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Code meaning

Duane53

Active Member
I have what I think might be a small problem. Then again it might be more. My check engine light comes on when I start the bike and then goes out shortly after it has run for a short time. I checked the codes and U1097 Loss of Speeometer Serial Data EFI comes up. I have been looking to see what that means and I can't seem to find anything. Can anyone enlighten me?
Thanks
Duane
 
When the Host (ECM) communicates with the speedo or Turn signal module, it does it over a pair of wires just like a hard wire copper phone line. The data that is sent, is checked for errors. If errors are detected, usually the data will be resent. If communication between the two continues to fail, or a "state of health" signal is not received by the host, an error code will be set.
The data is sent in a "train" format, therefore it is called serial data. What year bike.
 
Since the bike is several years old, there is a very good chance the problem is an oxidized connector at the speedo or ECM. I do not have a set of prints for your bike but I would view the schematics and see how many connectors are between the speed-o and ECM. There probably are only 2 but I would check just in-case. Unplug the speedo head connector, inspect, clean and micro-motion lube the connector. I would also do the ECM connector. The schematics will be very clear which connectors and pins are responsible for serial data.
There is a very good chance it's a poor electrical connection and that may fix it.
 
I would use Part number 99861-02 (Nyogel 760G) for the contact lube. Designed especially for these types of problems.
 
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