K40 relay module - Unplugging Connectors
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z50,ew350,950sm,450exe,525exc,t120,t140,98lowrider,W210E55
K40 relay module - Unplugging Connectors
Having some "will not crank" issues with my W210 E55. Many postings point to problems with the K40 relay module located by the ECU, passengers side. So I thought I'd remove the module and check the circuit board. I'm having a struggle unplugging the smaller electrical connectors on the module. Is there a trick to this? The larger connectors have clips with press tags, but not so for the smaller ones. I dont want to apply too much brute force to such small components.
Thanks in anticipation.
Thanks in anticipation.
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z50,ew350,950sm,450exe,525exc,t120,t140,98lowrider,W210E55
Thanks, but I've tried any number of blade devices. The problem is I cannot see where to insert the blade to trip the catch; assuming this is the way to d0 it.
Last edited by mcgyro; Feb 16, 2015 at 08:24 AM.
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z50,ew350,950sm,450exe,525exc,t120,t140,98lowrider,W210E55
Thanks
WD40 a rubber band (to hold in the tabs), long nose vice grips and some brute force did the job. Replacing the K40 relay fixed the starter problem; I could see burnt diodes on the old PC board.
Cheers
WD40 a rubber band (to hold in the tabs), long nose vice grips and some brute force did the job. Replacing the K40 relay fixed the starter problem; I could see burnt diodes on the old PC board.
Cheers
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W109 300SEL6.3, W123 280TE, W123 200T, W210 E55
Passangerside module box ... there is also the Motronic, ESP/BAS/PML, Transmission Control Unit and if you have this extra the ADS Control Unit located.
greetings, Fabian
greetings, Fabian
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Joined: Aug 2009
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From: Maine
2000 W210 E55 AMG, 1959 W180 220S
Thanks Fabian,
I found it last night (much too late) and all looked well there. I did however have some burning on the ECU so I'm working through how to replace that now. Thanks!
I found it last night (much too late) and all looked well there. I did however have some burning on the ECU so I'm working through how to replace that now. Thanks!
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2021 Yukon XL Denali, 2017 GLS450 4MATIC, 1993 Chevy Corvette
housew - what symptoms are you getting causing you to look into this? Just curious as I am having issues with intermittent start and stall right now and the K40 module is a potential area to check.
Junior Member
Joined: Aug 2009
Posts: 67
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From: Maine
2000 W210 E55 AMG, 1959 W180 220S
car shut off mid drive (~40mph, 45ish miles into my drive) and wouldn't restart. I can turn the key but won't crank. I thought the K40 would be worth checking.
My radiator fans come on in position 2 even when the car hasn't been run for days so that's what caused me to look at the ECU and find the burnt components.
My radiator fans come on in position 2 even when the car hasn't been run for days so that's what caused me to look at the ECU and find the burnt components.
