[DeobandiPrince]

Hey All,

My BMW doesn't want to start. When I put the key in the barrel and push the clutch down and press the start button, I can hear the fuel pump prime but no clicking. I tried replacing the starter and same issue. I'm getting codes a0b3 and a0b4.

I can get the car starting with a push start and popping it into gear but can't depend on this method all the time.

FYI my car is not equipped with an IBS sensor from factory.

I also tried hot wiring the starter as shown in the image below (with pin 4 of that green connector with the white wire that goes directly to the starter straight to the + terminal post in the engine bay) and it would get the starter to spin immediately after which the car would turn on but that method no long works.


Also, for a while, once you push started the car and popped the clutch, you could turn the car off and it would turn back on as long as you didn't wait too long. If you let the car sit for like 5-10 minutes, it wouldn't start again and would have to push start it. But now that doesn't work either (I mean to say once you turn the car off, it stays off no matter how fast you turn it back on)

I tried replacing the big black fuse in the glove box fuse box in the top right corner (I believe it's called terminal 30 relay.) It does get warm when I try and start the car multiple times. Not sure what other fuses and relays to check though.

Am ready to have it towed to a indy with good google ratings who say they specialise in euorpean cars but wanted to see if anyone here had any idea before I go ahead with it later this week

[Guy Fieri]

Worth checking your ground cables

[DeobandiPrince]

Originally Posted by Guy Fieri

Worth checking your ground cables

Any particular ground cables I should look for? There's the one directly on the body of the starter but are there any others that may affect it?

[DeobandiPrince]

Hey guys. Still at a lost of what I can look into. If you guys have any ideas or potential things I can check or data/INPA info I can provide, please let me know.

[Suvorovo]

Any chance you didn't buy genuine BMW bolts for the starter. I don't think people have issues with rein bolt either. Some cheap starter bolts don't conduct current.

[Serf27]

Did you check your battery?

[chilledn52]

Starter relay? Or Dead spot in Starter?

[desertman123]

Unless your ground straps are really bad, your CAS module is probably toast. Those codes are the tell. Has it ever sounded like a relay is going crazy?

Mine went out too, apparently it's an increasingly common thing. Pull it out and send it off to someone on eBay. I sent mine off and they told me the unit was fried, so I grabbed another from the junkyard and they cloned it for like $120. You need to send off the DME and keys along with it - all these are paired together.