Accessory plugs in engine fuse box
09-03-2015, 07:29 PM
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2009 ML550
Accessory plugs in engine fuse box
In the engine compartment's fuse box there are three receptacles for (what I assume are) spade connectors. They are F123 (blue), F124 (red), and F125 (black).
I have not yet gone in with a multimeter but I have seen references that blue or red are hot when the ignition is on (position 2).
Questions:
1. What is the difference between red and blue?
2. Is black a ground?
3. What is the amperage rating of the red and blue receptacles (and black if not a ground)?
Thanks,
- CJ
(I am adding a Stebel compact air horn to the factory horns. My wife had two Stebel Magnums in her 2001 ML320 and - while the ML550 horns are louder - she wants closer to the old power)
I have not yet gone in with a multimeter but I have seen references that blue or red are hot when the ignition is on (position 2).
Questions:
1. What is the difference between red and blue?
2. Is black a ground?
3. What is the amperage rating of the red and blue receptacles (and black if not a ground)?
Thanks,
- CJ
(I am adding a Stebel compact air horn to the factory horns. My wife had two Stebel Magnums in her 2001 ML320 and - while the ML550 horns are louder - she wants closer to the old power)
Last edited by BaddogLT; 09-04-2015 at 11:45 AM.
