m80
MB Enthusiast
- Joined
- Apr 26, 2015
- Messages
- 5,705
- Location
- Derbyshire, High Peak
- Car
- Viano ex long, 651 2014. S211 646 2009 (till the Gov't drones blow 'em off the road)
Since owning the van the alarm hasn't worked correctly.
Lock it and the hazards flash continually until the fob is pressed to lock again.
I bought a new sounder, there wasn't one in place. No difference.
The 12 volt (charging) to the sounder is ok.
All alarm functions, doors, passive detectors, bonnet switch, tow sensor, all cause the hazards to flash when the van has been locked. So the alarm is working, but no siren.
DAS talks of a testing unit, or oscilloscope, to test. There is suggestion of a DC pulsed output (from the o/h light unit I think).
Can anyone explain to me what I should be looking for at the 3rd pin at the sounder?
Having looked at the online drawings for the alarm system I don't believe there to be an additional alarm control unit. My belief is that the o/h light unit is the controller. The sounder has an integral battery hence the charge supply, and the 3rd pin would be to initiate sound.
Is this a line taken to -ve (chassis) at the light, or a pulsed input from the light unit?
Lock it and the hazards flash continually until the fob is pressed to lock again.
I bought a new sounder, there wasn't one in place. No difference.
The 12 volt (charging) to the sounder is ok.
All alarm functions, doors, passive detectors, bonnet switch, tow sensor, all cause the hazards to flash when the van has been locked. So the alarm is working, but no siren.
DAS talks of a testing unit, or oscilloscope, to test. There is suggestion of a DC pulsed output (from the o/h light unit I think).
Can anyone explain to me what I should be looking for at the 3rd pin at the sounder?
Having looked at the online drawings for the alarm system I don't believe there to be an additional alarm control unit. My belief is that the o/h light unit is the controller. The sounder has an integral battery hence the charge supply, and the 3rd pin would be to initiate sound.
Is this a line taken to -ve (chassis) at the light, or a pulsed input from the light unit?
