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Hi everyone,
Based on Calibenz’s posts, I’m wondering if it’s possible to use variant coding to route the intercooler pump to the ignition circuit so that it’s always on when the ignition is on.
I’ve already switched to the Pierburg CWA 100.
Cali mentioned that he uses a Launch C Reader for Mercedes-Benz. Could this be the correct one: https://amzn.eu/d/0i61PUj6
It would be nice to go a way with coding, because ECU Tune can't do that.
If you’re looking to get into coding on these cars, one of the easiest and most cost-effective ways is to use a cheap Tactrix clone (around €25 on AliExpress) together with CaesarSuite (https://github.com/jglim/CaesarSuite/tree/main), which is free. It runs on Windows, so if you’re on macOS, a basic Windows laptop (or similar setup) would be needed.
If you’re looking to get into coding on these cars, one of the easiest and most cost-effective ways is to use a cheap Tactrix clone (around €25 on AliExpress) together with CaesarSuite (https://github.com/jglim/CaesarSuite/tree/main), which is free. It runs on Windows, so if you’re on macOS, a basic Windows laptop (or similar setup) would be needed.
I have a Tactrix OBD Dongle, VCX SE, Xentry, Vediamo and Monaco. But I don't know where to find the settings for activation of this IC pump. And I'm not skilled in Vediamo and Monaco, in this case would help someone who can via remote do that. But it's important to know which codings are the way to go.
What is this CaesarSuite? I never saw this tool, but it sounds good.
I have a Tactrix OBD Dongle, VCX SE, Xentry, Vediamo and Monaco. But I don't know where to find the settings for activation of this IC pump. And I'm not skilled in Vediamo and Monaco, in this case would help someone who can via remote do that. But it's important to know which codings are the way to go.
What is this CaesarSuite? I never saw this tool, but it sounds good.
You might want to check out CaesarSuite on GitHub (the link I posted earlier). It’s a pretty interesting tool. Rnd-ash — the guy behind UltimateNag52 — has also been involved. He reverse-engineered the 5G-Tronic TCU and built his own controller, so these guys definitely know what they’re doing.
I don’t currently have access to a working car to verify this, so take it as a starting point rather than a confirmed solution. From what I can remember, our C218 uses the W212-based architecture, so you should be looking at SAMF_212.
I came across parameters related to the auxiliary water pump (ZWP = Zusatzwasserpumpe). You can open variant coding (Vediamo, DTS Monaco, or CaesarSuite) and look for VCD_Parameter_Zusatzwasserpumpe. There are options such as ZWP_Ein_KL15, which would suggest running the pump with KL15 (ignition on).
I don’t currently have access to a working car to verify this, so take it as a starting point rather than a confirmed solution. From what I can remember, our C218 uses the W212-based architecture, so you should be looking at SAMF_212.
I came across parameters related to the auxiliary water pump (ZWP = Zusatzwasserpumpe). You can open variant coding (Vediamo, DTS Monaco, or CaesarSuite) and look for VCD_Parameter_Zusatzwasserpumpe. There are options such as ZWP_Ein_KL15, which would suggest running the pump with KL15 (ignition on).
That said, I haven’t actually tested this.
I will check out that CaesarSuite Tool. Thank you.
Today I put a cable to the Ground of the relay like @kenneyd did in his Video, to run the pump (CWA100) always on. After that I went for a ride and was shocked, how high the air intake temp. was in my Xentry. It started fron 45 °C and went to about 70°C with 1-2 soft pulls. I think this is massively to high for these kind of engine. 😔 Maybe there is a air pocket in the intercooler system or something like that. Or what you think about that? Maybe it's important to do a vacuum job on the system, to keep out the air. 😤
Today I put a cable to the Ground of the relay like @kenneyd did in his Video, to run the pump (CWA100) always on. After that I went for a ride and was shocked, how high the air intake temp. was in my Xentry. It started fron 45 °C and went to about 70°C with 1-2 soft pulls. I think this is massively to high for these kind of engine. 😔 Maybe there is a air pocket in the intercooler system or something like that. Or what you think about that? Maybe it's important to do a vacuum job on the system, to keep out the air. 😤
According to your write up looks like your IC pump is not running at all. Are you 100% sure you did get it running after the pump swap? Bosch 010 will run on the "test table" when just put power in it. CWA100 won't do that. I have tested that by myself. It needs pressure. You need to pump the pressure in the pump. Like push the hose that is connected to cwa100 with your hand and make the pressure. I did rub my head badly with this but @Cifdig did help me out back in the day. I did thought that the CWA100 is broken from factory but surely it wasn't.
According to your write up looks like your IC pump is not running at all. Are you 100% sure you did get it running after the pump swap? Bosch 010 will run on the "test table" when just put power in it. CWA100 won't do that. I have tested that by myself. It needs pressure. You need to pump the pressure in the pump. Like push the hose that is connected to cwa100 with your hand and make the pressure. I did rub my head badly with this but @Cifdig did help me out back in the day. I did thought that the CWA100 is broken from factory but surely it wasn't.
I think you might be right.
Maybe it'll help if I apply pressure to the expansion tank. I just ordered a kit so I can apply pressure or vacuum to the system.
You can test does the pump work or not easily. Just connect the "always on mod" wire. No need to even start the car. Just pop the hood, take IC reservoir cap out, install the magic wire with care. Open the cars door so the power comes in for few minutes and you will see is the liquid moving in the reservoir. After that you have the answer.
You can test does the pump work or not easily. Just connect the "always on mod" wire. No need to even start the car. Just pop the hood, take IC reservoir cap out, install the magic wire with care. Open the cars door so the power comes in for few minutes and you will see is the liquid moving in the reservoir. After that you have the answer.
The pump can also be easily turned on using Xentry. No wiring or anything
Of course but not everyone have Xentry in their garage including me.
From what I understood, Slobo has those tools handy We need to hook you up with some diagnostic tools at some point though. I've said it many times before, too.
I have all these tools, and according to Xentry, the pump or relay is always set to "On." But I think there might be air in the system and the pump isn't pumping any water at all. When I look into the intercooler's expansion tank, nothing is moving, in my opinion.
The CWA 100 is so quiet and vibration-free that you hardly notice it.
I have all these tools, and according to Xentry, the pump or relay is always set to "On." But I think there might be air in the system and the pump isn't pumping any water at all. When I look into the intercooler's expansion tank, nothing is moving, in my opinion.
The CWA 100 is so quiet and vibration-free that you hardly notice it.
Okey, when there is not any movement with water not any Xentry would help you. You need to make the pressure. Heh and my way would be just squish the hose that goes to the pump and there you go. Hope you get it running soon.
Btw. there is one really important thing that I forget to ask you. Have you check the fuses? I have put 7,5A fuse to use CWA100. I will burn the oem 5A fuse. But if it is burned is your own decision to use 7,5A.
Btw. there is one really important thing that I forget to ask you. Have you check the fuses? I have put 7,5A fuse to use CWA100. I will burn the oem 5A fuse. But if it is burned is your own decision to use 7,5A.
Here are the IC cooling systems side to side. Base M157 vs. M157 S ( M157 + M 014)
Now we can see that the extra (smaller) HE lower hose would go to the intercooler. Looks so.. It's number 550 in the picture. And that hose part number is A2125017284. (Only S models)
I haven't found what part number hose will go from CWA100 to extra HE. Just found a part of the hose. It's number 600 in the picture. Part number is A2125017084. (Only S models)
This confuses me what kind of hose set is that picture 520? is it connected to the 600 somehow? Must be for what I think.
M157 vs M157 S ( M157 + M 014)
In the hose diagram 550. Part number A2125017284.
In hose diagram number 600. Part number A2125017084.
Last edited by PekkaH; Mar 24, 2026 at 07:31 AM.
Reason: Typo
Here is one picture that I found from net. But can't see straight where the IC pump hose is connected to Heat exchanger.. In that M157 + M014 IC system pictures that long hose 550 that I linked picture looks like to be connected to heat exchangers lower connector. Still no clue what is the part number for hose 520 that should go from IC pump to this heat exchanger. All other part numbers are clear.
Now I know what hose is that upper HE hose. This is solved now. Here is the part number A2125015484. It have the same connection style to CWA100 like to extra IC HE. Also now we can be sure that hose from CWA100 is connected to extra IC HE upper side and lower connected to main IC. So AI was wrong in this case. CWA100
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