PDA

View Full Version : HFS4 coil whine when set to DR1


HenryM
22-09-2019, 10:52 AM
Hello Richard,

I sent you an email about a month ago but haven't received a reply so I'm posting on this forum.

I have a 2011 BMW 335i with N55 PWG engine and I've got a few questions for you:

https://youtu.be/EutKQbGr0cc

When the CEL jumper is set to DR1, the controller board makes a loud buzzing noise as soon as I insert the key.
The noise won't stop until pulling out the jumper from DR1.
I would like to know if this is normal. Everything else works fine if I set it to DR0.

Richard L
26-09-2019, 08:29 AM
the DR1 should not be used with car with EWG, email me so I can set you the correct diagram.

HenryM
26-09-2019, 05:45 PM
the DR1 should not be used with car with EWG, email me so I can set you the correct diagram.

Hello Richard,

I have a PWG and I used this diagram I found on this forum:
http://www.aquamist.co.uk/HFS4/wiring/BMW/H4-v3.1-N55-N_EWG.gif

Except the two red wires from the 'POWER INPUT' and the 'ECU' harness.
I tapped them from the cigar jack lighter fuse instead because I noticed the red/green 12v feed from the ECU wakes up as soon as I insert the key and stays active even after shutting down the engine and removing the key.
Instead of dropping down to 0v immediately, it stayed at 12v for a while (30 seconds to a minute from faint memory) and start tapering down to 2v slowly.
I didn't think this observed behavior is ideal as a switched power source so I avoided it.