robdata

Right. Have the same problem as discussed in previous threads with intermittent power loss. I did ordered a new pump but still have a couple of questions .
1} does the pump only start when the coolant riches a certain temperature ?
2} where is the fuse
3} where is the relay
4}how do you know which fuse is what. On my previous bens was a paper legend inside the lid.But in c32 nothing
Thanks for any help

02C32guy

I believe the pump is pumping as long as the car is on and a little bit after it's been turned off. If you search, you will find multiple places where I have posted the fuse diagrams in PDF format (There's three).

robdata

Right after running around with the Multimeter I found
1} its fuse number 5 in the boot
2} its relay no c

robdata

Just to help other people who struggled like me, I thought I would make a small picture thread.

1) The fuse board and relay are in the boot on the left hand side (for IC Pump) The arrows indicate the dedicated fuse and relay for the IC pump.


2) After I checked the fuse I pulled out the relay to check if it is working correctly. As you can see on the photo, the two ports for the coil gave me continuity which indicated that the relay coil is OK. The other two arrows indicate the actual switching point to energise the pump.


3) To check if the relay switch works properly, I did a little trick. What I did was to use two spade bits to stick in the contacts of the relay port to connect an amp meter to see if the pump is pulling any current, which in my case was dead.




4) After I replaced the pump which was faulty (for a peace of mind) I would like to indicate to other use how to check if the pump is working or not. As you can see on the multimeter, the new pump pulled 2.8A in my case (and a noise could be heard of the pump working).



5) Everyone is looking for the fuse board chart. After browsing the internet for days I finally found it. It is hidden in the cockpit.



I hope that this is a good guide for people that struggled like I did!
I took the old pump apart and could not believe the problem.The brushes where down and I spend 260 for new pump. Brushes properly a 10 er

02C32guy

I posted the three diagrams in post #2 and #4 of this thread.

https://mbworld.org/forums/c32-amg-c...-no-sound.html

kinginsaab

Hi, I have the same issue with my intercooler pump, when I check my fuse box in the trunk, no fuse in location #5 ans no relay in the port C. Did check the paper in the front door for fuse #, and it say that my fuse for water pump (AMG) is #18 witch I did have a 10 amp fuse...

All the info i find is about fuse #5, not 18...
On my fuse designation paper, it's written model# A). I have a C32 2004 (Canadian model, don't know if it makes a difference).
Question, is there someone else with the fuse #18 fir the intercooler pump? or it's all about #5?..

thank you for your help

02C32guy

The fuses you need to be concerned with are the ones labeled "Charge Air Cooler Circulation Pump (M44)"

See the diagrams posted above.

kinginsaab

Ok Thank you for the info, I guess I will need to put a 7.5 amp in fuse #5 and find the rely to place in port C (according to the post above). But can someone tell me what is the relay # I need in port C for the ic pump, and were can I find one?

thank you for the help

Greger-meister

Not really sure you need a relay. The current draw is only 1.9 amps from what I understand. Do you not want the pump running all the time?

kinginsaab

Well, I realy don't know, the only thing that I'm sure at the moment, is that I don't have a fuse in the location #5, and no relay in the positon C. And from the all the post above, its' seems that we need a relay in C??

What I find strange, is that on my fuse designation paper (the paper find inside the fuse box on the driver side), I have no item on the fuse #5 (no water pump AMG- kompre), it's on #18 (see PDF)??? Why 18 and not 5 like anybody else???

I'm suspecting something strange; I change my water pump because I thought that it was dead, but I may have a missing fuse for all that time (I bought the car end a Feburary and here in Quebec, it was still winter anf very cold (5-10F), so I guess I didn't need the pump that much, but tnow it's getting hotter and I dont' feel the kompressor anymore... that's why I change the pump suspecting a dead one, but I'm just a little confused by this #5 fuse and this relay ''C'' VS what my paper say (#18)...

robdata

I just had a look on my plan and it seems to be different to yours.On myn is deff. number 5 and c relay in the boot. I have 2003 model

kinginsaab

Looking at this old thread (http://m.www.mbworld.org/forums/show....php?p=1309712

Vadim at Eurosport seems to say that around 2004, MB remove the relay for the ic pump in the E55, and just use a fuse. Could it be the same case for the 2004 C32?

No relay, just a fuse (10 amp in my case in position #18 and not in the positon #5 @ 7.5 amp. like in 2003 and before)??

robdata

have you had a tester on the fuse or on the pump cables?

kinginsaab

I will do it tomorrow at work,

Robdata, can you tell me what is the # or the detail written on your relay at position "C"? I'm not able to read the details on it from the picture. I called the stealership here in Quebec city and the don't seems to have a clue about the specific # of the relay that goes into that position, I would like to order one, so it will be very helpful if you can give me the info written on it.

thank you for your help

kinginsaab

Ok I did check at lunch time if my pump was running. I use the same process you did robdata, sticking 2 blade spade into the relay connection in port ''C'', with the car running after and after a 10 minutes drive to make sure the pump had a chance to start. The multimeter gave me 0 amp. when i checked. I had a brand new 7.5 amp fuse into the location #5 also.

sound like the pump is not running.... it's a brand new ford Ligntming pump, bought last week, and did check last night that it was well connected and nothing special, everything look fine.

I guess I need to take of the battery of my wife's car and unplug the connector of the pump and check if it run directly foprt eh battery... But I have a very hard time to belive that this brand new pump is not working, almost impossible...

robdata

Did you ever measured the voltage direct on the connection of the pump on the pump ? That would save you dismantling the pump.

kinginsaab

Hi, just a follow up, I did last night check some fuse in the front SAM in the engine bay. I did change 1 fuse (#51) that was looking kind of strange(rust or humidity that have dry with some dust, but no visible braking in the fuse), I decided to change it anyway. By looking into the fuse chart, it's seems that #51 is involved somehow with the M44 (ic pump).

After that, I did start the car, place on "D", and with the foot on the brakes, increase RPM to 1500 so the sc can engage. I did eared the clutch of the sc engage.

Then, stop the car and go around trying to ear the ic pump... and I did!!! it ran for around 20 sec, after the engine was stop!

I guess problem solve.

thanks every body for your help

robdata

Wonderful another happy customer

jonrph77

FYI very important update to intercooler pump issue on c32. I have changed my pump, but it was still not working. I drove the car without pump for about 3 to 4 years now and everything was fine, no break downs. Many years back, I took the car in to the dealer for another issue and apparently, at that time, the tech pulled my fuse and relay switch out and pushed it back into wrong slots. Thus, even with the new pump, still no go. It took 3 days to look through fuse box and diagram as well as another post and pics of other people's rear fuse box to figure out how to complete the intercooler issue on c32 models up to 2003 models. 2004 c32 apparently uses fuse in #18 instead of #5...

Open the fuse box in trunk and look for rear ebox in driver side. open up the panel and foam and on fuse #5, should be a 7.5amp fuse. check to make sure this is still good. then need to check to make sure relay next to it which is in 3rd from top position at bay C is still in the fuse box. (a correct relay switch should be black in color and have 4 prongs, in 2 + 2 perpendicular position.) Mine were empty as the MB dealer tech plugged mine back from fuse #5 into #7, and simple relay C to relay D(a white relay, not a relay switch). Relay D should be the only empty relay socket in terms of relays. If this is fully done with new pump installation, then Everything will work like magic. Remember, before doing any intercooler repair, check this step first. Even with new pump, no fuse, no relay, no go. Also, I was told by dealer that these 2 fuse/relay would normally be replaced when intercooler pump is repaired at their shop. So, maybe pick up new relay C and fuse #5. relay is about 25 bucks and fuse cheap. FYI, no one sells the relay on the internet, need to hit the dealer for this one unfortunately, so no part number is required. Oh, I called the dealer and they say that bay C is in their system as brake off switch or something like that, not intercooler relay switch. Hope this post will save a dude like me a whole lotta time and headache. Bosch SVT lightning pump works like a champ and also, no need to switch pump pipe housing either. Just get some new hose metal bolt clamps and the original hoses fit right into the new pump and no leaks. Use a large wrench and pry off old pressure clamps, and use new bolt clamps. Takes like a minute to do the pump swap.

Rock_Wen

There was an IC pump issue on my C32 last month.
After changing IC pump and check the fuse #5 and relay in the rear SAM, the supercharager still didn't work.

The engineer assume the rear SAM or front SAM have some problem but no error code beside (M44 IC pump power short ground etc...). The engineer add a relay between front fuse box (fuse of key start position) and IC pump using the wire directly to battery.
When the key is on ,the IC pump is started with battery power without pass through SAMs.
But the supercharager still wasn't worked.

Thanks God!
Finally , acoording the fuse chart in this site, I rechecked front and rear fuse #5, #7 #51(looked normal and exchanged with #49 the same amps) and #18 (there is NO relay on C and D in the rear SAM) in the fuse box and found my #18 fuse was broken.

After replace #18 (exchange with #5 7.5A) and all function runs well and got lose power back!

This result shows the SAM and FUSEs are different from years!
Thank you for who provide fuse chart in this side.