Wont Crank Unless I Have A Jumper Pack On The Enginebay Positive

[wrongturn]

I checked the BST and it has not been detonated. My car has been in a front end accident. 9 times out of 10, it's a bad bst but not this case. I scanned it for codes and nothing jumped out at me. It just clicks without the jump pack

[Hallerhan]

I had this issue on my n54 335i (however it was not in an accident). My issue was fixed when I replaced my starter and the engine bay/chassis ground cable

[FBloggs]

Assuming that your subject is an E46 M3, have you checked the circuit breakers above the fuses?

[eacmen]

Check grounds.

[sapote]

Also, when I do get it to crank, it won't start. Any tips? thanks

The EWS (anti-theft module) maybe blocking the engine from running. You need to verify this by using INPA software tool to read the EWS codes.

Once the engine got back to running, then I can help to fix the cranking issue.

[eacmen]

The EWS (anti-theft module) maybe blocking the engine from running. You need to verify this by using INPA software tool to read the EWS codes.

Once the engine got back to running, then I can help to fix the cranking issue.

If it was EWS it wouldn’t crank right?

Maybe the ECU out of sync with EWS?

I would also check voltage at engine bay pos terminal without the jump pack connected. The cable from the pos terminal that goes across the engine bay goes to the starter.

[wrongturn]

I haven't checked the grounds yet or the EWS. Snapon scanners should be able to diagnose it instead of INPA, right? I have a triton d10.

If it was the EWS, would that mean the engine won't start even with the jump pack? I just found out that someone stole the fuel pump from my car so that explains why it wont start with the jump.. Copart special 🙄

[sapote]

If it was EWS it wouldn’t crank right?

Maybe the ECU out of sync with EWS?

I would also check voltage at engine bay pos terminal without the jump pack connected. The cable from the pos terminal that goes across the engine bay goes to the starter.

Could be EWS and DME out of sync

Once it runs, will ask him to measure the batt voltage and the jumper post voltage and compare. This will tell if there is significant volt drop from jumper post to batt, or drop across the BST.

[sapote]

I haven't checked the grounds yet or the EWS. Snapon scanners should be able to diagnose it instead of INPA, right? I have a triton d10.

If it was the EWS, would that mean the engine won't start even with the jump pack? I just found out that someone stole the fuel pump from my car so that explains why it wont start with the jump.. Copart special 🙄

EWS connector can be easily shorted out to have the starter cranks, but this won't help the engine to run if there is EWS issue.

[George Hill]

Definitely not an EWS issue.

If the starter just clicks it is likely because you are not getting all the battery juice to it either by a voltage drop or something consuming amperage (often the same cause).

Is the engine ground good?

Have you checked 12v at the jump point?

Where are you putting your negative lead from the jump box?