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Exorcising an electrical demon

2132 Views 28 Replies 8 Participants Last post by  Avel Du
Hello all

Former (and still) British car owner here. And a proud new SLK owner. I have owned British cars for decades, and a German car for only weeks.

I have another (could be the same) electrical demon and wish to banish it from this plane of existence. I wonder if my Mg infected it, it is quite possible as they are ripe with electrical diseases.

My foglights turn on several minutes after the car is off, and flicker. I am not too familiar with Morse code. But it seems to be summoning Cthulhu.

I wish it to stop for all our sakes.

Damned infectious British cars!

Anyhow, I have candles and a phone number for some Benedictine Monks that have promised to bring their 'A Game'. I just need a PSE a vacuum pump, I think...... Or is there something else I should try? A relay..... maybe some sacrificial virgins in a volcano..?

British cars weren't so picky, you know... any volcano will do... Germans, well methinks not.

Ohh... and there is this strange flickering / chattering on the drivers side like a relay off and on really quick that makes the button that disables the alarm turn off and on.

Different demon?

Can I battle them solo in combat, do you think? Special weapons and/or incantations?


Cheers!
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fyi, moved your thread here from general discussion to this section, the r170 general discussion because, tada! you have a r170!


future issues with your car, please make a thread in the r170 general discussion section, not the general discussion section

the general discussion section is for slk discussion but NOT model specific. Your thread was model specific.

Thanks

JB
Sweet sassy mallassy I have a caretaker.

Thanks buddy!
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Thanks for becoming a lifetime member so quickly! wish I had a cut!
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I think you are in the right direction with regards to the PSE. Have you given yours a look? I think you can clean them up sometimes without replacing them and be good as new.

Sorry you have had British cars for so long >:D Welcome to Deutschland!
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I think you are in the right direction with regards to the PSE. Have you given yours a look? I think you can clean them up sometimes without replacing them and be good as new.

Sorry you have had British cars for so long >:D Welcome to Deutschland!
I'm sorry too.... but only somewhat... I do love a FUNCTIONING British car.. They are quite sexy. Tempermental. I have Vatican on speed dial for issues regarding the gremlins.

Any suggestions on possibly rebuilding the unit?

I'm fantastic with a soldering iron.
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I'm sorry too.... but only somewhat... I do love a FUNCTIONING British car.. They are quite sexy. Tempermental. I have Vatican on speed dial for issues regarding the gremlins.

Any suggestions on possibly rebuilding the unit?

I'm fantastic with a soldering iron.
The British can make a good looking car. The Germans can make a well engineered good looking car.

So it is quite interesting. The two most common issues on the R170 is the K40 relay and the PSE. Neither of which I have had personal experience with, knock on wood.

I think this is a good place to start. http://www.slkworld.com/slk-r170-class-diy/115065-pse-removal-refit-check-turn-over-required.html
Thanks for becoming a lifetime member so quickly! wish I had a cut!
Finder's fee?
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The British can make a good looking car. The Germans can make a well engineered good looking car.

So it is quite interesting. The two most common issues on the R170 is the K40 relay and the PSE. Neither of which I have had personal experience with, knock on wood.

I think this is a good place to start. http://www.slkworld.com/slk-r170-class-diy/115065-pse-removal-refit-check-turn-over-required.html
Know any inexpensive PSE's.... As it may be a **** shoot.
Know any inexpensive PSE's.... As it may be a **** shoot.
Personally, I have never shopped for a PSE. I think you can get a new one for about $500. I would take a shot at it, especially if you know your way with a soldering iron.
The British can make a good looking car. The Germans can make a well engineered good looking car.

So it is quite interesting. The two most common issues on the R170 is the K40 relay and the PSE. Neither of which I have had personal experience with, knock on wood.

I think this is a good place to start. http://www.slkworld.com/slk-r170-class-diy/115065-pse-removal-refit-check-turn-over-required.html
Where is the K40 relay? is it attached to the unit..... If so... is in my right hand or left..
I pulled a relay off the PSE ....Siemens not Lucas. My Spidey sense says its alright.
I'll check to make sure.

The K40 was the attached relay, yes?
Where is the K40 relay? is it attached to the unit..... If so... is in my right hand or left..
I pulled a relay off the PSE ....Siemens not Lucas. My Spidey sense says its alright.
I'll check to make sure.

The K40 was the attached relay, yes?
No the K40 relay is in the main box if tricks ender the bonnet, remove the lid and there is a mass of wires the k40 relay has a big 40amp fuse on the top next to a bunch of standard fuses, you also need to remove the bottom of the PSE to check the circuit board for corrosion.

Regards Stuart.
Got to jump in this thread and make my disparaging remarks about British cars, Lucas electrics and John Lucas, the prince of darkness.

Now that's out of the way, here is a video I found on the K40 relay. One note: this is a right hand drive car, so if yours is left hand drive, it will be on the opposite side of what is shown in the video.


Tim
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First things first - get the Italians out of your speed dial. If youre calling Italy in for divine car intervention it won't end well for you!

Methnks you have multiple problems.

Start with the fuse box under the hood, the fuse panel will lift out in its entirety and reveal a small control module on the side of the box. Is this the source of the clicking relay? While you're in there, inspect the fuse holder with good light and maybe a magnifying glass.

German electronics suffer from poor soldering in their mass production "wave soldering" processes. The joints just don't hold up over time. It's very common to fix components by simply re-heating the solder that's already there. Especially in the units that carry higher current like the K40 unit which switches on and off some very pervasive circuits.

These cars have rain drains that clog and seals that fail to seal, and both cause all manner of water incursion problems. Keep your eye out for any moisture induced corrosion while you're in there. And go ahead and clean those 8 drains now even if you don't find any. Moisture kills the PSE, often due to clogged drains under the spare and behind the rear wheels.. It was foolish for MB to put that thing in such a low spot.
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k40 pulled

Got to jump in this thread and make my disparaging remarks about British cars, Lucas electrics and John Lucas, the prince of darkness.

Now that's out of the way, here is a video I found on the K40 relay. One note: this is a right hand drive car, so if yours is left hand drive, it will be on the opposite side of what is shown in the video.

https://www.youtube.com/watch?v=70b-LJsbFqk

Tim
I pulled the k40 relay.

There appeared to be a bit of scorching on one (same) soldered contacts. It looked to be fine otherwise. I re-soldered the contact.

Fingers crossed

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Solder

Upon applying the soldering iron, the solder melted immediately, then re-hardened meaning its heat absorption just increased. Meaning that it may not have been visible but there became more metal to wick away the heat.

Soldering iron medium low setting.
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The alarm tow away disable light is still red........ lights aren't flashing . confused
Have you removed and inspected the PSE next to the spare? The typical K40 symptoms aren't alarm and fof light related. Alarm issues, and errant exterior lights on, are more typically due to PSE issues.
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Has there been any projectile vomitting of "pea soup"? If so you need a young priest and an old priest! They'll put some holy water in the radiator for ya! Good luck battling the forces of evil.>:D
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The alarm tow away disable light is still red........ lights aren't flashing . confused
When you were in the boot locating the PSE pump there is a small relay bolted to the web just behind the pump, that is the towaway sensor check the connections, if you remove and tilt it the alarm should go off, if not then faulty sensor or wiring.

Regards Stuart.
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