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Parasitic Current Draw - W124 300CE 1989

Old Jan 30, 2026 | 03:06 PM
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Parasitic Current Draw - W124 300CE 1989

I have a 1989 W124 300CE with a parasitic current draw of 3.5 amp. I have removed all fuses in the fuse box and the fuse for the blower motor but the draw is still there. Are there any other fuses in addition to those in the fuse box? Any suggestions of where else to look or how to look for the problem
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Old Jan 30, 2026 | 05:50 PM
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Originally Posted by Lilanda
I have a 1989 W124 300CE with a parasitic current draw of 3.5 amp. I have removed all fuses in the fuse box and the fuse for the blower motor but the draw is still there. Are there any other fuses in addition to those in the fuse box?
Any suggestions of where else to look or how to look for the problem
Thanks
Now you need to use your chassis ELECTRIC DIAGRAM to follow what circuits is powered by what fuse protection.

See the PORTAL-DIAGNOSTOV free schematics at...
portal-diagnostov.com if you will.

Many modules can remain partially powered.
It's easy to waste time checking dead leads so its best to stay focused at this stage.


Last edited by CaliBenzDriver; Jan 30, 2026 at 06:02 PM.
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Old Jan 31, 2026 | 05:31 AM
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Originally Posted by Lilanda
I have a 1989 W124 300CE with a parasitic current draw of 3.5 amp. I have removed all fuses in the fuse box and the fuse for the blower motor but the draw is still there. Are there any other fuses in addition to those in the fuse box? Any suggestions of where else to look or how to look for the problem
Thanks
Which fuse box? there is a couple places that have fuses.


Last edited by RobertR728; Jan 31, 2026 at 05:37 AM.
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Old Feb 5, 2026 | 01:45 PM
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Thank you very for the help, it was the alternator. Should have realised this earlier as it is one of the few things that don't go through a fuse.
Will take it in for repairs today
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