pmgiarrizzo

Has anyone ever swapped out their old pump with a Johnson CM30 and STILL not have the pump turn on?

I've searched and tried every damn thing there is. This is what I've read, everyone seems to have a different idea:

1 - Pump should run all the time (ignition pos 2)
2 - Pump doesn't run until driven hard past 2000rpm
3 - Pump doesn't run until driven hard past 2000rpm and then stops running when car stops (say at a red light, or car is turned off)
4 - Pump has its own fuse and relay (where?)
5 - Pump does not have fuse and relay, and is run purely off of ECU.
6 - Pump runs when engine gets up to normal operating temperature
7 - Pump turns on when supercharger is engaged for the first time and then stays running until the car turns off.

The list LITERALLY goes on forever. everyone has a different approach and different idea and different solution. CAN WE PLEASE make this a helpful thread for anyone with issues like this?

I have tried every single scenario here and NOTHING gave me 12volts at the pump. the pump works and runs fine with a battery I had sitting around. A few guys have simply "skipped" this whole whoopla and just ran their own switched 12volt circuit. that's great, and I'm almost going to go that route, but I'm as stubborn as they get and need to know why this pump wont turn on.

can someone please shed some light. I've checked CLS forums, ive checked e55 forums ive checked C32 forums... all im left with is a small amount of dignity and a tonne of motivation to get this taken care of.

I'd like to at least get the pump going on the OEM circuit and then have STAR diagnostics at a local dealer program to have the pump run continuously as the car starts (ignition 2)

thanks,
Pete.

pmgiarrizzo

also, in case I can't figure out what the eff is going on, does anyone know of any switched 12v circuits inside the engine bay fuse box? i know there are 2 positions for a fuse for the cigarette lighters... switched and constant??

equitiesguy

The below is from watching the system from the motor electronics, driving around with Xentry plugged in.

Pump does not engage when you first start the motor. It engages the first time the supercharger clutch engages. Make sure your supercharger clutch is engaging at all and there isn't something wrong with it (should be able to "feel" it or plug in STAR to verify).

After that it runs constant and never shuts off until the ignition is shut off, whether you come to idle or not (supercharger clutches disengages at idle, reengages at approximately 40% engine load).

Should be able to put your hand on the pump or on the hoses and feel it running. The pump doesn't pulse very hard because of the rubber mounting its in, but the hoses definitely do.

In the CLS 55 the "charge air circulation pump" (stock setup) is driven off relay N10/2kA (reference gf54.15-p-1256-06txa in WIS). The fuse is the 7.5amp FUSE in the REAR SAM (4th up from bottom left). The N10/2kA relay is the bottom right relay marked A in the REAR SAM.

Hope that helps.

pmgiarrizzo

That is excellent information. Here's where my story might change things.

So I've looked in the back fuse panel. the 4th fuse is not there. i have 3 fuses and then a blank. The bottom right black relay "clicks" on. i have placed a 7.5 amp fuse in there and STILL have not received voltage at the pump. I did drive the car up and down the street once or twice pretty hard to ensure that the supercharger kicked in, and beleive me, it did, the tires were lit up with ease..

any suggestions after knowing this?

thanks again
Peter.

equitiesguy

Change the relay. Change the pump. You won't be able to get a volt reading off the pump wiring unless you leave the car running after driving it, unplug it, and check it. Assuming that doesn't throw an error code, you might be able to check it that way.

pmgiarrizzo

I've had the car running with the pump disconnected, no error codes, no issues what so ever. Ive had the car running long enough to get it up to normal operating temperatures (water temp gauge in car reads between 80 and 90 degrees celcius as normal) i then took the car for a rip up and back down the street to attempt to get the pump to run, no such luck.

i tried reading a voltage off the leads, nothing. 0.001-0.002VDC.

I spoke with Eurocharged Canada, they said depending on the ECU Coding and Software Version, every car runs the pump at different times, some always, some after running etc.

so unfortunately it doesnt solve my issue, but at least i know im not going crazy when i say ive tried it all and it still doesnt work.

Every one seems to run a dedicated circuit to the pump, I'm starting to lean towards that side. I can use the cigarette lighter fuse spot since it apparently has 2 positions ignition on, and constant on. I can use those two signals to trigger a relay to run the pump as soon as the ignition is on.

thanks for everyones help. Ill hopefully post results this weekend.

equitiesguy

The pump runs when the supercharger engages. Have you swapped from the default clutch pulley? The activation signal comes from the motor electronics at the same time.

Are you running a different tune than AMG's? If so, it's possible they've screwed up something royally.

If you want a thread to help others know what the normal operation of this stock Bosch pump is, then using Eurocharged Canada's opinion of "the pump runs whenever it wants" is not logical. Why wouldn't the pump run when the supercharger engages? Would it want the inter-cooler temperatures to get up to 200f before it turns on? The answer is no. Clearly whomever you were speaking with was confused. The pump keeps the intake air as cold as possible so the moment you hit the throttle, the car is running as cold as it can be.

I would check the electrical leading up to the pump again (4th fuse slot from bottom left, not the 4th physical fuse (it could easily be missing) / and double check the relay by swapping it with another one), plug in STAR and do a proper diagnosis.

You won't receive any error codes with the pump disconnected unless you get the IAT well into the point where the supercharger is overheating (180f+).

If you are swapping to a separate electrical circuit I wouldn't bother bashing your head into the wall --- just set it up the way you want it to run and don't worry about it.

pmgiarrizzo

I appreciate the response, but I didn't ever say that Eurocharged said "the pump will run whenever it wants". Eurocharged said the pumps will run at different times for different cars based on their ECU software version.

I have nothing tuned yet. the car is still on the OEM configuration. All I did was remove the old pump and put in the Johnson CM30 pump.

I have decided that I'm going to run my own electrical circuit, simply because I don't know anyone (aside from dealerships) that have STAR diagnostics. The only reason I want to get the pump running on the original circuit is so that I can sleep at night knowing that the car does not have a problem with that circuit. It seems as though there are so many different aspects to the car that are all tied together and I just don't want this to be a hassle later.

I plan on using one of the circuits inside of the engine bay fuse panel. Fuse 53 (i measured with a multimeter) has 2 positions the fuse can be in. It has 3 poles, left, middle, and right. The middle pole shorts out to ground, perfect. The right side was a constant 12Volts, and the left side (towards engine) is a switched 12Volt Circuit. Currently the fuse in there is a Blue 15A, and it is in the "right" position using a constant 12volts. I plan on using an inline fuse kit like this:



And swap the 15A fuse for a 20A fuse to accomodate the extra current consumption of the pump. the switched 12V signal will activate the Relay coil, and the constant 12Volts will then be delivered to the pump when the car starts.

If any one would like pictures, please let me know.

vvrjrlaw

I'd urge you to invest in some higher end diagnostic equipment if you plan to handle maintenance on your own. There are a number of Star systems available for under 500.00. Just check the Internet. That said for me personally the fact that the system doesn't function as intended from the factory requiring a separate circuit would drive me nuts. Just my OCD. Good luck with the modification and I hope it works for you.

pmgiarrizzo

Your OCD is the same as my OCD. I didnt realize STAR systems were around the $500 mark... i figured they'd be in the thousands. In that case, once i have all of this settled, i just might get myself a STAR system

Thanks.

vvrjrlaw

It's absolutely worth the investment. Trust me you'll be glad you did. Good luck.

equitiesguy

I took a photo of mine just so you can compare if you want to track this down later. I second Vince's suggestion -- if you want to do be able to do any of this yourself, having STAR makes all the difference in the world.

I checked your VIN you sent me on WIS specifically, and the Canadian car has the same wiring as any other CLS55 AMG, including mine. M44 (the intercooler pump) drives off the same fuse (F4 rear SAM) / relay.

Rocman8

replace the relay!

pmgiarrizzo

Here's a pic of my rear fuse panel, I can confidently say that Fuse #4 was never there. This was the first time I've ever opened the fuse panel.



As you can see, the Relay is in place, however, no 7.5Amp fuse. Very weird.

vvrjrlaw

The relay is there but the fuse isn't. Someone opened that fuse box. Maybe not you but someone did. Put the fuse back in and see what happens. In theory the fuse completes the protected circuit and should permit the electricity to travel to the relay awaiting actuation by another trigger or sensor. Does the relay pins show any voltage? Use a DVOM and connect the black to ground and use the red ( positive) to probe the relay socket to see if there is power. If not leave the relay out put the fuse in and do it again. You should have power. Check with the ignition in the on ( but not started) position. Good luck.

hvacdude

I'm very familiar with trouble shooting car electrical circuits. Here is what I would do if I owned your car: Turn the key all the way to the right, don't start the car.
#1 Start at the source/fuse {power supply}.
Put a volt meter lead on a good ground. Take the other volt meter lead and touch it to both sides of the fuse sockets, one at a time. One of the terminals should make the volt meter read 12volts. That establishes power is coming into the fuse block for that fuse.

#2 Put a good fuse in and check out the relay.
Most of the relays {Bosch} have 5 pins. Two of them are for the coil of the relay {#85 & #86} . When the coil is powered {12volts to #85 & #86}, it closes the contacts {#30 to #87}. The contacts send power to the device {IC pump}. The relay is configured like this: #85 & #86 are the pins for the coil. #30 is power in, #87 is normally open, #87a is normally closed.
#30 on the relay is where the power from the fuse feeds into the relay.

#3 Put one meter lead on a good ground and the other lead in the female socket that #30 on the relay plugs into. You should see 12volts. Check all the terminals. You should see 12volts on one or two of the female relay sockets.
If you have 12volts on #30, then power is going to the relay and you can "jump" it to send power to the IC pump.
To "jump" the relay, I take a small piece of wire and crimp male spade connectors on to both ends of the wire.
Put the "jumper" into where #30 and #87 on the relay plugs into the relay socket.
You should now be sending 12volts to the IC pump.

#4 Put your meter leads on the wires that feed to the IC pump. If your meter leads are to big to fit in IC connector, unfold a couple of paper clips, and stick them in the female connector sockets. Put your meter leads on the unfolded paper clips. You should see 12volts. If you have 12volts, the pump should run. If you don't see 12volts, try pushing your sharp meter leads right into the wires that feed into the female IC connector. If you then see 12volts, the connector is bad.

In summery, you need to confirm that you have power to the fuse block, power from the fuse block to the relay, jumped out the relay too send power to the pump. If you loose power in any of these steps, you have to trace back the wires and connectors to see where the power is, then is not. This is basic for trouble shooting any circuit. There may be other switches that are between the fuse and the pump. It's always best to have a wire diagram that shows the flow of power to the device your checking out.
I had the same problem of super charger not kicking in. I had 12volts at the female IC pump connector. I just changed the pump and was good to go.
I think you said you put a new pump in, make sure your new pump is good. put 12volts directly to it and see if it runs. Do this before going thru the check out procedure I just spent a hour describing. Good luck, and I hope my advise gets your pump going.

hvacdude

A couple of questions. You said the relay clicks when you put it in. Was the car just started when you did this ? Was the engine warm ? My understanding is; when you start the car {cold start} the super charger is engaged . The engine runs at a bit higher idle than normal for about 30 seconds, then settles down a bit. That's what mine does.
From what I have learned about our cars, the super charger doesn't engage until the engine gets up to 3000 rpm. I don't know if the SC pump cycles off, and doesn't run unless the engine is over 3000 rpm, or if once the SC has been engaged it runs all the time, or if the pump is running once the engine gets to a specific temp. I do know that something or some condition {temp, RPM} makes a relay send power to the pump when the SC is engaged. I could see the relay click if you checked it within 30 seconds of a cold start or if the engine was warmed up. If the relay clicks, that's a good sign that whatever controls the relay is working. If the intake air temp switch shuts down the SC, it could be a bad pump, a restricted cooling system, a bad temp sensor. The pump could run, but not turn the impeller. Take the pump out and put power to it and look down into the impeller and see if it turns. Jump the pump relay and see if it runs when hooked up to the factory wiring.... shouldn't be that hard to track down unless the circuit between the fuse and the pump has a broken wire or splice, or the flow of coolant is restricted or the temp sensor is messed up. Also, you said the fuse was not there. Maybe it blew when ever the fuse was in. Does the fuse blow when you put it in ? Does the fuse blow after the engine is started ? does the fuse blow after the engine runs over 3000 rpm ? If the fuse blows you cold have a short to ground. Ohm out the pump. or disconnect the pump and jump the relay and check the power lead for continuity to ground. You could wire the pump "hot" That's not a proper fix. You want it the way it was ment to be out of the factory. You need to track down the circuit and find the break, or short, or control that stops the pump from working. You might even have a bad SC clutch or clutch wiring issues or switch that engages the clutch. You could hot wire the IC pump, just to see if the SC kicks in when you nail it. That would rule out the SC circuit.
I bought a bluetooth OBD reader and software that connects to my smartphone so I could see if my intake air was high. I think The IA temp should be 30 to 50 degrees higher than ambient if the pump works. I noticed my car had no ***** when I nailed it on a hot day. I bought the OBD reader and software and saw the IA temps were way high. That's when I first learned about heat soak and known issues with the IC pump on our cars.

pmgiarrizzo

hvacdude, I really appreciate your time and efforts through replying to this thread, I did exactly as you said (I too spend a lot of time diagnosing electrical circuits) and before reading your reply I was already pulling the relay and checking everything from fuse voltage and relay signals.

Here's what i found, the fuse DOES have 12V coming to it. So the measurement from ground to one side of the fuse socket is +12V. Cool, straight forward. The other side of that fuse shorts (or shows continuity) to the relay, perfect, that would be the constant 12V in that will switch over (30 & 87) and continue to the pump.

So I mentioned the relay "clicking" yeah.. it clicks alright. its like a baby fake crying. you hear it... but you know its not real... sure enough. I pulled the relay, I powered it up on an external battery, the poles 30 & 87 DONT SHORT. dammit... stupid a$$ relay.

guys, change the damn relay first. just do it, okay? cool.

I still ran a new circuit to avoid the whole "when is it actually running" question. now it runs when the car is in ignition 1 (cigarette lighter on). so the pump will run constantly, which is what i wanted it to do from the beginning.

equitiesguy

Mercedes relays are notorious for failing on the power side. I'm unsure as to why you ever had a blank in fuse 4. Glad to hear you finally swapped out the relay and that was the culprit.

pmgiarrizzo

Yeah Germans are fantastic mechanical people, they're logical and very realistic. But when it comes to electronics... they should leave that game to the pros. The Japanese have some of, if not the most, advanced electronic developments in the world. I've seen audiophile equipment made in just about any country, and when you open up the hood on an amplifier or pre-amp on a USA made or anything european... first impression, damn thats clean... open up a Nakamichi or Japanese made... and you'll see real artwork.

same goes for cars I suppose :P. anyways, everything functions like OEM, but im not using the OEM setup.

again, i cant thank you guys enough for the input. lets keep this up to save everyone time, money and problems in the future!

cheers,
Pete.

equitiesguy

There's nothing wrong with German electronics, particularly Bosch. Having a relay defective that's been monkeyed with is no surprise (proof of that is the fuse blank in the slot that may have been hotwired at some point, or who knows what before you obtained the car).

The japanese electronics in cars is borderline garbage. Even the chrysler parts on this car are better than the "MAKE MY CAR GO BY ITSELF" motronics from japan (they should've used Bosch).

At least it works :p.

I love my Yamaha sound system btw in my home theatre.