BMW M5 Forum and M6 Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter #1
Hi ,
my e34 m5 1992 3.6 doesnt do a flap test when starting.
New vacuum lines new solenoid .
flap opens when directly connected to 12 v.

What possibly go wrong
i have 2 modules and both not working.
How to test them what part may fail.
Opened them both the boards are good no bad connections and not burned.

Rpm is also working fine.

What else shoukd i check ?
thank you
 

·
Registered
Joined
·
743 Posts
1. Ignition ON, do you get ~12V on the wire that goes from the solenoid of the resonace flap to the control unit?
2. Ground the wire that goes to the resonance flap and see if it operates
3. Power and earth OK
4. Does the TD wire get to the module? Can you hoop up a LED tester to see if it blinks while the engine is running?
 

·
Registered
Joined
·
22 Posts
Discussion Starter #3
Hi thank you ,
We have snow here i will test today.

What is the TD wire?

I ll get back to you with results for the above tests

Regards
 

·
Registered
Joined
·
22 Posts
Discussion Starter #5
Hi again,

Test result:
1-ingnition on 12v exist.
2- No ground available.
3- Wire of ground is good to control module.
4-Engine on if grounded the valve it opens never close unless i remove the vaccum line .
Also never close if i turn off the engine. Note it moves free by hand its not stuck.

Any idea ?

Thank you.
 

·
Registered
Joined
·
743 Posts
I don't get exactly what you mean. Therefore I made a point to point test which I hope you can perform again...

Resonance control unit pin out:
  • 1. Blue/Black – resonance valve
  • 2. Brown/Black - throttle position full load input
  • 3. Black – engine speed input
  • 4. Brown/Orange - Ground
  • 5. Green/Violet - Power supply

Do the following, access the resonance control unit (placed together with the DME in the BOX under the hood on the right side).

  • 1. Use a voltmeter and turn it on voltage measurement (DC) and put black/ground wire from voltmeter on pin # 4 (ground) and red/positive wirre to pin # 5 (power supply). Turn on the ignition and engine. The resonance valve is power by the fuel pump relais and is only activated shortly during ignition on and permanently with a running engine.
  • Do you have ~12V?
  • 2. Remove the red wire from voltmeter and put it in pin #1 (resonance valve). Do you have 12V?
Leave the black / negative wire from the voltmeter connected to pin #4 (ground) during these measurements.

  • 3. Remove the red wire from voltmeter and put it in pin #2 (full load signal). Do you have 5V?
  • 4. If the engine is heated up or you want to Turn the throttle lever to full load, do you have 0V?
  • 5. Remove the red wire from voltmeter and put it in pin #3 (engine speed signal). Do you have ~12V?
  • If OK. Remove the wires from the voltmeter
  • 6.Get an extra wire and connect it to pin#1 (resonance valve). Short it to ground anywhere you like. The flap should be operated once you ground it.

I will try to make a manual for you as soon as possible with guide steps on how to identify problems. Please try the suggestions above and report back
 
1 - 6 of 6 Posts
Top