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K40 relay module

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#262 ·
Hi
Thanks for all the replies - So is the facelift K40 module the same as the pre facelift and the crossfire K40 module ?
Because to my thinking they look different ! But I dont have access to both to compare side by side !!

Sinbad you say you have a 2003 which makes it a Facelift model - So have you done the soldering on your K40 module ? and if so what were the symptoms ??

Thanks
 
#264 ·
Hi

Thanks sinbad - that's perfect information. So we can say that this thread definitely applies to Facelift versions as well !
Thats good.


The small fault I have is that my SLK230 will be a little "kangaroo like" when cold - OK when hot though !



Also tick over has always been slightly uneven when hot. Gets a tiny bit worse when operating the roof !
Its not terrible - I just don't like it and I guess it will get worse over time.



Could this be k40 relay module related ??



Thanks
 
#265 ·
Part number for my pre facelift K40 is: A2105400072. But I was advised the K40 used on post facelift R170's are different.
 
#266 ·
Thanks Lowmoorfarm - You are correct - I did an internet search (images) and there are two different types.
I cant provide any part numbers as i don't have access to that kind of information.


So its getting more confusing !


I suppose the question is, do both types of K40 Relay module suffer from poor solder connections or is it only the pre facelift ??


The facelift K40 Relay module looks more difficult to take apart, and also appears to have an additional plug in relay on the top. So I am not sure about all this !!



Thanks
 
#267 ·
I had & have the Pre & Post facelift models. They both suffer from this problem & doesn't matter how many plugs, the issue is the 3x top LH solder points on the circuit board.

Since i had mine re-done by an Auto Elec (£10) neither car ever suffered from it again.

And the boxes are reasonably easy to open up, but tbh, just tell the Auto guy what & where it's wrong & let them open it up.
 
#268 ·
Healey said:
Thanks Lowmoorfarm - You are correct - I did an internet search (images) and there are two different types.
I cant provide any part numbers as i don't have access to that kind of information.


So its getting more confusing !


I suppose the question is, do both types of K40 Relay module suffer from poor solder connections or is it only the pre facelift ??


The facelift K40 Relay module looks more difficult to take apart, and also appears to have an additional plug in relay on the top. So I am not sure about all this !!



Thanks
Click to expand...
If you need the part number for your car, pm me your Vin and I'll see if I can help you out.

Sent from my ANE-LX1 using Tapatalk
 
#270 ·
Hi
Thanks to all - This is a great forum.


I think I now have the answer I was looking for from cockneyrick.



It looks the the pre and post facelift K40 Relay modules are different, but have the same soldering problems.


I wont get the chance to look at mine for another week, but I think I will take a look at the the solder joints and see if I can fix my issues.


Thanks again to all
 
#271 ·
I have a 230 SLK from 1999 with 130.000km. When do this problems start? Would it be wise to replace the K40 Relay before trouble starts?
 
#272 ·
ladyavenue said:
I have a 230 SLK from 1999 with 130.000km. When do this problems start? Would it be wise to replace the K40 Relay before trouble starts?
Click to expand...
Absolutely not! It will cost a Kidney to replace it. Just have the solder joints re-done @ a fraction of the cost.

And generally anything past the 100,000 can fail, but this is not hard & fast. It can happen on an old car with 50,000 on it :wink:

Which reminds me, I must put mine up for sale, as i have bought an ML350 so i can get in & out easier due to my fooked hip :frown:
 
#273 ·
Padgett said:
Well I have some part numbers: SLK320 (post facelift) A 170 545 03 05, (pre facelift) A 210 540 00 72. From pictures (have the 0305 but not 0072) the fuses look the same but the box shape is different. Used ones seem to go for U$65-U$75,
Click to expand...

Why would anyone buy a 2nd hand one, knowing
1: It's old,
2: Could fail at any time,
3: The easy option is £10 tops!
 
#274 ·
Does K40 relay also caused the engine cooling fan not to run and cause overheating? Replace thermostat ,low coolant level sensor, top off coolant, check fuse, check fan control module and they were fine.
 
#275 ·
Well chaps!
Its been a while as I have done less than a 1,000 miles in the silver machine. I have had it stored whilst my garage has been used to repair boats. I collected my car from storage, which I had left on a trickle charge system to keep the battery healthy. Did the usual checks after being off the road. Drove 6 miles and the engine cut out as described above, dash board lights a blaze, engine fan spinning away. Started after a while but it happened again. Knowing I had checked the K40 relay and all "looked" with the naked eye great, i discounted that as the cause. After some sole searching and some forum reads from you guys, I revisited the K40, took a magnifying glass to the top left solders, hey presto!!! as described and presented by Woolly in the above picture. A touch of solder on each of the three and problem solved! I could just hug a tree... so simple but such a headache. HUGE thank you guys!
 
#276 ·
What is the part number of my 2001 slk 230 's k40 relay? thank you also i need to order one so a lik to a US based retailer would be great. thank you all in advance.
 
#277 · (Edited by Moderator)
#278 ·
any idea why my 2001 slk230 would have a different part number on the one installed in it? 1705450305 from what i can find this appears to be for a slk320. unless i am mistaken
 
#279 ·
The part number i posted is from your vin
305 would be a replacement from 205...
 
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