86 SEI Fuel pump Nightmare

[4Beckett]

Hello all, I am new to the wings and to this forum and I decided to start with a complicated girl

My 86 SEI is giving me some headache and maybe some SEI/LTD owners can shine a light on this case

I bought it as a non runner, replaced the dead alternator, no start, the cruise control light on the dash always on, no signal from the ECU lights either,
So I went the tested it output voltage arriving to the pump, only 7v applied 12v from an external source and the pump ran, pushed stared and the bike started right away!
The only thing left was to clean the contacts, replace the dog bone fuses, check all the relays ( all are fine) and last time I checked the power at the pump and got the 12v back!
went to bed and the next day, no power at the pump at all!
here is what I did

• tested for power from the battery to the fuse box and its getting 12v alright
  tested all the relay sockets and they all are getting power but the relay socket is not getting any
  ECU doesn't show anything
  The bike won't start anymore, even with 12v external applied to the pump making it run.
  Checked the Grounds, All fine, the cruise control light went off

If somebody knows anything like it please let me know, I have researched a lot but every case is a new case so I thought about asking around
thank you in advance!

[Rednaxs60]

Welcome. I have an '85 Limited Edition FI model. First you need the manuals, without these you will be chasing your tail so to speak. You need the OEM/Clymer service manual(s), Electrical Troubleshooting manual, and the Supplement.

You mention that you have checked/changed(?) the dog bone fuses. There is a wire connected to the battery terminal of the starter solenoid that has a 30 amp dog bone fuse on it for the CFI system. If it is faulty, no power to the CFI system.

When you turn the key to on, does the dash light up and go through what looks like a test. You should see all lights on the right side of the dash light up, and go off in a sequence: cruise lights first, then Fuel System, Then the upper light goes off and the oil light stays on. The neutral light should also be on.

You should also hear the fuel pump start and pressurize the fuel system for about 3 seconds. It will turn off but will start automatically as soon as the engine is started.

The Fuel System light is not what it implies. It is the equivalent of an automotive check engine light, and has nothing to do with the fuel system - just is. The CFI system is such that the ECU - located under the trunk - has a built in self diagnostic program that checks for signals from the FI system sensors. If there is no signal from a sensor an error code is generated that you can see from the left side of the bike. There is a small window in the side of the ECU and you can view the lights. An error code will stay on and can be viewed as long as the key is on. If you turn the key off the error code is lost, the ECU does not have a memory function. The error code may show up when you next turn the key on. If there is an error code the Fuel System light on the dash will light up.

First check the CFI dog bone fuse.