[sbrmaint]

I have a 2008 Yamaha VX1100 Sport (with 450+ hours) that has an engine temperature sensor that is acting up and regularly throwing a code. All our efforts to diagnose the issue have failed to eliminate the alarm from going off when driving the ski. Hoping someone else might have seen a similar problem and may notice something we missed. Note on a properly functioning ski, when you unplug the engine temp sensor, the Yamaha Computer Diagnostic System (CDS) registers the sensor as being unplugged; on this ski when you unplug the sensor, the CDS says the sensor is still plugged in and out of range...

So far we have:

0. Checked engine temp. All is within normal operating spec.
1. Replaced the temp sensor w/ new
2. Checked wire continuity from temp sensor plug to ECM (black w/ yellow)
3. Replaced temp sensor wire (black w/ yellow) going to ECM
4. Checked ground wire continuity from temp sensor plug to ground bus (black w/ orange)
5. Rerouted ground wire (black w/ orange) from ground bus on fuel rail directly to block
6. Swapped ECM's with a known good ski - ECM from bad ski worked fine on good ski (no codes); ECM from good ski showed same problems as original when plugged into bad ski
7. Swapped multifunction meter (speedo gauge cluster) with known good

None of the above fixed the problem, but we eliminated the ECM as being bad, the temp sensor as being bad, and the wiring associated with the temp sensor as being bad. Now I'm at a total loss as to what needs to be checked next... Never seen this problem before. Anyone have any ideas?

 

[steve berube]

temp sensor issue

I think your problem is in a CONNECTOR related to the temp sensor. That is the reason that the diagnostics show out of range rather than disconnected. in other words, one wire--possibly a single strand--is touching something it should not be. Continuity will be fine; checking grounds will be fine; but, when it's all live, the ECM is reading milliamps(as is the diagnostics) and that slight crossover//short//feedthru is being picked up resulting in your alarm. Your post doesn't specify whether you replaced connectors but I think that's where you need be. Don't miss any and don't take anything for granted.
GOOD LUCK!!!
Let us know how it turns out...REMEMBER: If man made it, man CAN fix it!!!