Is my ECU FUBAR?

johnhorsley5

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I had to replace the fuel pump and level sensor unit on my 99T 1150GS because the green wire to the pump had overheated and snapped. I was using a work around with a pair of spade connectors but wanted to tidy it up. (stupid man)

Before putting it all together I bridged the male and female connectors with wires so that I could test the new pump and level sensor. I must have done something wrong as the 10A fuse for fuel pump relay popped.
I replaced the fuse, but still no pump. The level sensor is OK

12V is present at the fuse. The supply through the ignition switch and kill switch seems OK, so it looks as though the Motronics unit is not enabling the relay. The relay has 12v from the kill switch on one side and a connection to the ECU on the other.
Have I destroyed the Motronics unit? or is there another reason there is no 12v at the connector to the pump?

The new pump has been sitting dry for a year. Is it safe to run either of the pumps dry, to test them? Can I put water in them rather than petrol?
 
I have...

Fuses are OK.
Swapped relays around.
Next is to test the old and new pumps without blowing myself up (ie away from petrol fumes)
 
Hmmm...the only reason that a wire would overheat and snap is if it is carrying too much current, shirley? This suggests that whatever is on the other end (the pump, in this case) is fubar, or one of the connectors on to the pump is offering a large resistance. Can't see that this would have a 'downstream' effect on the ECU, being as it is protected by a couple of fuses. Or at least, one would hope not...!
 
Sorry, I'm not explaining the chain of events well.
Shortly after I bought the GS, the pump stopped working (short version). The dealer found that the green wire in the tank connector had fractured and so they extracted the cores from the bundle either side of the plug & socket and made a spade connection. This green wire looked as though it had been overheating.

Fast forward to this year.
I bought a tank with less dents and scratches and also had bought a while ago a replacement pump and level sensor module (with good connector)
Problem: How to test the new tank and module with good socket against the loom and plug still with the spade connector? I made a set of short patch leads so that I can connect all four cores.
That's where I may have cross-connected the patch cords, as the pump few blew. I have replaced it. All the fuses and relays are good (I think) but there is no 12v at the green core to the pump
 
success

For anyone who might be interested, the problem was that the "new pump" was FUBAR. I don't know if it was faulty when I bought it as part of the module last year, or it has jammed through being dry for that time.
Next time test the part if you can when you take delivery.
Now that I know the pump etc is good, I can consider fitting the replacement loom
 


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