Electrical Issue with pump power

[sf4018]

Another track day, another breakdown. All was good on track then fuel pump cut suddenly. Fuel pump has no electrical power, inertia switch is ok but has no power either, so it’s upstream of that. Fuses are all ok. ECU is bypassed so it’s not that. Everything else is functioning normally. Anyone have any ideas?

[JohnCh]

I'm not sure how this is wired, but if the relay is upstream of the the inertia switch, have you confirmed it is getting power and switching correctly?

 

-John

[sf4018]

You were on the right track, it’s a loose wire on the pump relay. I jiggle the relay around and I can hear it click and the pump goes on. Same if I wiggle the wires behind it. Just gotta figure out how to fix it in the field.

[sltous]

I had a loose connection in the fuel pump relay at the black plug before the grey plug connecting the MFRU to the vehicle loom.

 

Some guidance at https://www.lotus7.club/forum/techtalk/cut-out-and-now-wont-start.  Looks like pin 13 in the grey sumitomo plug, although my problem was corroded pins one plug towards the main harness from this plug.

 

[sf4018]

On 10/30/2021 at 2:07 PM, sltous said:

I had a loose connection in the fuel pump relay at the black plug before the grey plug connecting the MFRU to the vehicle loom.

 

Some guidance at https://www.lotus7.club/forum/techtalk/cut-out-and-now-wont-start.  Looks like pin 13 in the grey sumitomo plug, although my problem was corroded pins one plug towards the main harness from this plug.

 

Thanks so much @sitous and @JohnCh for the pointers, I managed to get her running again and save the weekend. 🍻