[chiefwolf34]

Only reading 2 volts going to the fuel pump and if I hook up 12 to the pump it runs. Under the hood the small red wire on the black plug below the relays only reds 2 volts. Any help?

 

[chiefwolf34]

Would like to know where the red wire goes before tearing the machine down to manually trace.

 

[chiefwolf34]

Already disconnected the key switch not it.

 

[chiefwolf34]

Thinking it's got to be straight off the battery because I still show 2 volts at the black plug with the key switch removed and the key switch just sends it to a relay.

 

[chiefwolf34]

Okay anyone with a tech manual can you tell me where the red wire goes from the key switch?

 

[chiefwolf34]

So please excuse my earlier post on this that pesky red wire I was looking at goes to the light switch. With that said can someone tell me which relays on the circuit board under the front hood are for what?

 

[Bradhill]

Sorry I do not have a copy of the Tech Manual for the 850i RSX.

Good luck!

 

[chiefwolf34]

Thanks anyway Brad I did figure out that the problem is with the relay module.

 

[Bradhill]

Thanks anyway Brad I did figure out that the problem is with the relay module.

Great news!!

 

[chiefwolf34]

So after doing some more troubleshooting found that along with no fuel pump the machine has no spark and nothing going to the injectors.So I can assume it's the ecu. Found signs of water on the board. Bad news out of the way can anyone on this group explain to me why in the name of all that is holy is there a vent on the cover of the ecu?

 

[chiefwolf34]

Okay after some reading the vent is to equalize pressure inside the equalize pressure inside the Ecuadorian during extreme temperature. The problem with the design is the adhesive on the back side is failing allowing water and dirt to get inside from a simple washing. Very sad design flaw or very smart at $743 for a replacement.

 

[chiefwolf34]

Hate spell check

 

[benpack61]

Hate spell check

was the ecu the problem or the relay under the hood for the fuel pressure?
having similar issues

 

[200mph]

Their root cause may not be yours. Suggest you use a voltmeter and trace the voltage along the path to conclusively determine. If uncertain how to use voltmeter there are a number of good videos on YouTube showing the basics. Yours could be a cut wire, while there’s was an ECU issue.

Most electrical problems on this forum are due to corroded connections anywhere along the electrical path and not part related. Testing can save both time and money.

the technical manual has excellent wiring diagrams along with how to test the electrical components.

 

[chiefwolf34]

Yeah It ended up being a relay that is part of the sealed board under the hood. Picked up a used one from powersport nation.