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fuel injection relay, non functioning fuel pump Tue Jun 21, 2022 2:00 pm
geoff barnett
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Gentlemen, help is requested please.
The bike: K100LT, 1990, vin number 0179060, FOUR (4) pin Fuel Injection relay (rare but not unheard of).
What's wrong? Fuel injection relay problem and non functioning fuel pump.
The engine cranks over on the starter. No noise from the fuel pump turning. I know it's operative because I've taken it out and tested it very briefly with a battery. I am following Crazy Frog's famed fault finding post.
Neutral light is good, as is the clutch switch, as is the FOUR pin FI relay (12v across pins 85 and 86 elicits a healthy click), ignition switch is healthy, kill switch is healthy (disassembled and cleaned). Fuses are good.
There used to be 12v at the 4 pin petrol tank plug. Not any more.
I've swapped out the ICU for a known good one.
The big problem appears to be no power to pin 86 or 85 of the FI relay .
The wire to pin 86 of the FI relay is yellow/brown. It appears to connect to pin 7 of the female lead to the ICU. There is no continuity between pin 86 and female pin 7.
I don't want to rig up a new wire between female pin 7 of the ICU and pin 86 of the FI relay.
I'm not afraid to check the HES having recently replaced the same on my R1100RS.
Any thoughts on the malaise of the K100LT will be appreciated.
The bike: K100LT, 1990, vin number 0179060, FOUR (4) pin Fuel Injection relay (rare but not unheard of).
What's wrong? Fuel injection relay problem and non functioning fuel pump.
The engine cranks over on the starter. No noise from the fuel pump turning. I know it's operative because I've taken it out and tested it very briefly with a battery. I am following Crazy Frog's famed fault finding post.
Neutral light is good, as is the clutch switch, as is the FOUR pin FI relay (12v across pins 85 and 86 elicits a healthy click), ignition switch is healthy, kill switch is healthy (disassembled and cleaned). Fuses are good.
There used to be 12v at the 4 pin petrol tank plug. Not any more.
I've swapped out the ICU for a known good one.
The big problem appears to be no power to pin 86 or 85 of the FI relay .
The wire to pin 86 of the FI relay is yellow/brown. It appears to connect to pin 7 of the female lead to the ICU. There is no continuity between pin 86 and female pin 7.
I don't want to rig up a new wire between female pin 7 of the ICU and pin 86 of the FI relay.
I'm not afraid to check the HES having recently replaced the same on my R1100RS.
Any thoughts on the malaise of the K100LT will be appreciated.