REX Won't turn on

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Hi, I have the same problem with the rex not starting after the car had stood for a while. I can occasionally get it to run but mostly it won't. Can anyone tell me if the fuel pump relay is still behind the glove box on a right hand drive car? Thanks, Pete.
 
Yes the relay is the one on the right (the left one is the ventilation fan in the engine compartment) you can try swapping them over, pain in the a$$ getting to the relays
 
Thanks all for this excellent tip. The REX on my i3 (2016 UK model) was failing with 'misfire' and 'lambda sensor' errors, always occurring very soon after starting the REX - within about 1mi. About half the time it worked OK - if it got past 1mi then it would keep going indefinitely.

My local garage had tried everything in the BMW diagnostics process without luck, and could only suggest as a last resort to replace the fuel injectors - £900. So I did some internet searching and found this post, and sure enough replacing the fuel pump relay has fixed the problem. I opened the old relay and the contacts were badly burned. Poor design BMW.

For others with a right hand drive i3 (UK market) the relay is under the glovebox, so same approach to replacement as for the LHD (USA/euro) model. The relay is behind a ventilation duct so is a right pain to get at. Its impossible to see what you are doing, so you have to do replacement entirely by feel. I'm glad I had a USB endoscope to have a look first at what I needed to do.

Note on my car the fuel pump relay is the LEFT of the 2 relays, not right, as many people on the internet say. Maybe they flip the relays around for the RHD cars. Which relay was which was clear because when I pulled the right hand relay the car gave a fault about 'engine fan relay open circuit' and replacing this relay did not fix the problem, whereas when I pulled the left hand relay it gave a fault about 'fuel pump relay open circuit', and replacing this fixed the problem.
 
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