Was assisting another forum user and compiled a list of helpful posts so I thought I would put them here. Multiple links in one post to save search time.

Gonna be a lot of links and info here...read to gain an understanding. The non-AMG fuel pump relay is located in the Rear SAM. Do NOT use that relay to power the fuel pumps or you will burn it out quickly. You can, however, use the terminals 86 and 85 of that Rear SAM relay position to control the large (70-amp) relay that will actually power the pumps. The large 70-amp relay will need to pull its power source from the rear pre-fuse box located with the spare tire; you can ground the fuel pumps to any good chassis ground point.
Rear SAM original fuel pump relay position can be used to control the larger fuel pump relay (mounted elsewhere in the trunk). You will need to complete your own harness for this; plan on minimum 12-gauge wire and if possible, 10-gauge wire to power the fuel pumps; the fuel pumps draw 13-14 amps each and regularly melt wires and original 40-amp relay in the '03 through '05 E55. The relay solenoid terminal 86 and 85 can use 18-gauge or even 20-gauge wire as that circuit will only draw a quarter to a third of an amp. You can build a three-relay setup for dual fuel pump relays; a proposed schematic is in the thread "E55 fuel pump relay and fuse maintenance" which is listed a bit below.

See figure 15 and writeup for power in "run" position and the connection that rear SAM activates; you want the purple and blue arrow contacts.:
https://www.pelicanparts.com/techart...mp_Testing.htm
FWIW, the relay in the above article powers the heat exchanger coolant pump in the E55; in the non-AMG cars it powers the fuel pump.
For fuel pump replacement info see:
https://www.pelicanparts.com/techart...eplacement.htm
Remember, the E55 fuel pumps are located in the passenger-side saddle tank and the fuel filter/regulator is located in the driver-side saddle tank. Connections for the fuel gauge and the evap pressure sensor are located on the driver's side top hat.

EDIT 2026-04-02: '03 to '05 E55 use one relay to activate both fuel pumps. The '06 has two relays; one per fuel pump. The '06 uses a modified Motor Electronics Module with two connections to the fuel pumps (one per fuel pump relay). Per UncleBenz55, "2006 models both pumps runs during start up, but the second pumps turns off a few seconds after engine start. The second pump only runs under load or ~4000rpm+, which is activated from the engine ecu via the second relay." https://mbworld.org/forums/w211-amg/...ml#post9276653

Thread on rear pre-fuse in the E55 over the years:
https://mbworld.org/forums/w211-amg/...fo-update.html
You'll want to pull pump power from the rear pre-fuse box. Be sure to fuse the circuit just before the fuel pump relay per schematic below.

Schematic of the E55 fuel pump relay:
https://mbworld.org/forums/w211-amg/...ml#post8120332

Proposed three-relay design:
https://mbworld.org/forums/w211-amg/...ml#post7166909

Read the entire thread:
https://mbworld.org/forums/w211-amg/...intenance.html

Good info on fuses and relays in the W211 chassis:
https://mbworld.org/forums/e-class-w...les-chart.html

A bit of trivia to let you know if you have a fuel pump wired backwards:
https://mbworld.org/forums/w211-amg/...ugh-years.html

When reading WIS schematics:
Z connectors route power from the SAM to various circuits.
W connectors route to ground points.

E55 fuel pump physical layout.

 

Kinda fun going back and forth with the individual seriously upgrading the power in his car going from normally-aspirated to forced induction. Requires an increase in fuel flow so he's going from a single fuel pump powered by the Rear SAM relay A to a dual-pump setup from a W211 E55. So...the following shows ideas on how to make this fuel circuit upgrade. Discussion revolves around single large relay versus two smaller relays while using the stock Rear SAM fuel pump relay.

-Take a look at the proposed three-relay schematic, look at the single relay schematic. This post explains my reasoning for going from a single 40-amp relay/socket to a single 70-amp relay/socket.
https://mbworld.org/forums/w211-amg/...ml#post7164983

-The three-relay setup was a fall-back position for me. The single 40-amp relay literally melts when powering two fuel pumps. The 70-amp relay runs much cooler. I've been running a 70-amp relay for literally 8 years this June and currently have put 100,000 miles at an average speed of approximately 35 mph (instrument cluster data). That works out to almost 2900 hours of run time on the 70-amp relay. Cooler is better.
https://mbworld.org/forums/w211-amg/...ml#post7171418

-The stock 40-amp relay powering two pumps literally melted at 92,313 miles; the plastic case melts when temperatures exceed 300 degrees F. Multiple instances of the melted "'03-'05 model year 40-amp relay powering dual fuel pumps" in the W211 E55 sub-forum; one of the weakest links in the '03 to '05 models.

-Stock 40-amp relay and socket replaced at 92,313 miles; by 124,000 miles, the relay was showing temperature rise and to me that indicated incipient failure.
https://mbworld.org/forums/w211-amg/...ml#post7171418

-I have never seen a post complaining about a melted relay in the dual-relay '06 E55. I have also seen no posts about a failed 70-amp relay powering dual fuel pumps. Not to say it cannot or has not happened but I have seen no posts and this W211 E55 sub-forum has plenty of gearheads.
-FWIW, a 70-amp relay has a larger size package than the 40-amp relay so a different socket is used. They are not directly interchangeable.

-The three-relay design could utilize your stock relay in the rear SAM to trigger the add-on dual-relay package (one per fuel pump). It would actually simplify the design now that I think about it. Use the power wire to the fuel pump to trigger the new fuel pump dual-relay assembly. You could use 40-amp relays for each pump and separate 12-gauge power wires to each pump. Take the three-relay design and see in your mind's eye the first relay on the left is the rear SAM relay in the "A" position. The Rear SAM relay pin 87 currently powers your stock fuel pump. Cut that line and connect it to pin 86 (solenoid trigger) of the dual-relays powering the pumps. Fused power from the rear pre-fuse box connects to pin 30 of each fuel pump relay. Pin 87 of each fuel pump relay connects to a fuel pump.
-You can use an adaptor connector to connect the fuel pump relays to the fuel pumps. Just cut the adaptor into two pieces and use one end to connect your new harness to the pumps paying attention to polarity. First gen fuel pumps 470-17-94 are +/-/+/- on pins 1-4. Second gen fuel pumps 470-00-00 are -/+/+/- on pins 1-4. Adaptor cable is part number 211-540-07-00 (The adaptor cable just swaps two pins so the old harness matches the new pump pinouts).
-Also, be advised the connections on the top-hat of the dual fuel pumps have a nasty habit of overheating and melting the top-hat. Another place Mercedes could have improved the design.
EDIT: there are THREE generations of fuel pumps, not two. My bad. Took me years to learn. A post further down in this thread explains: https://mbworld.org/forums/w211-amg/...ml#post9183556

 

bb can you clear some inbox space? ty in advance

 

Working on my phone but I believe I managed to delete a couple of dozen messages to make room. I'll clear more once I get home...

 

And some more info...this is to clarify the differences between generations of pumps and filter/regulators.

-Look at the connectors on the lines between the pumps and the filter/regulators.
-The 1st gen fuel pumps have female sockets; 1st and 2nd gen filter/regulators have male fittings to connect to the fuel pumps.
-2nd gen fuel pumps have male connectors; 3rd gen filter/regulator has female sockets to connect to the fuel pumps.
-2nd gen fuel pumps will only work with 3rd gen filter/regulator and require an adaptor harness as the fuel pump wiring is different than the earlier fuel pumps.

 

For the filter/regulator, I recommend replacing it as a unit. If, however, you would like to attempt to replace just the filter there are two options. A Febi-Bilstein 39831 can be adapted and Creative Steel sells a drop-in filter. Be advised it is a PITA to rotate the top hat in order to remove it from the housing. I had to use a vise with mine being careful not to crack any of the plastic.
-Be sure to verify condition of the fuel lines internal to the tank! It does you no good to replace the filter only to have a cracked fuel line internal to the fuel tank!
-When you replace the filter/regulator as a new unit, the new lines are pre-attached to the new filter/regulator.

 

What about w211 E63 and w219 CLS63?

Im looking to replace my pumps now on a 2006 cls63 I searched 2007 cls63 on fcp and so on and the following part number comes up which also cross references to the vin of my car as correct in EPC: A2114703694


Thats a 550USD + pump set + shipping to NZ... getting pricey! I did my e55 for less than half that back years and years ago... Even rockauto doesnt seem to sell the cheap fuel units anymore atleast for w211/w219 m156 cars....

I have already replaced the filter in the sender cheaply with the febi filter that I originally found years ago and did a write up on that here for E55's.
Iv looked around and read up and not finding much info on these. Can I just put AEM 320lph or DW300 type brushless pumps in the oem baskets and call it a day?

So im kinda thinking as long as it has a capacity of 320lph or so and 80psi capable aswell as brushless they should work fine its just fandangling the fittings as none of the aftermarket pumps match the oem quick connector.

I see claims of them being pulse width modulated 2007 up but how do you pulse width modulate a pump with two wires going to it?



Am I just going to have to wear the expensive oem pumps or can I try fit the aftermarket ones and not get fuel rail pressure codes and so on on m156?

 

Here is where we need some M156 gearheads to add to the knowledge base.
-The E63 and CLS63 use the PWM modules; all the modules are doing is rapidly switching the current on/off to the pumps. There is an excellent description of it in WIS.
-If a forum member with an E63 has information on the filter and pumps, it would be good to start a new thread on the "E63 fuel pump circuit information".
-The above posted Febi-Bilstein part number most likely came from you. Years ago I found one thread on the Febi-Bilstein filter so I downloaded the photo and screen-shot the description. I usually bookmark relevant posts but multiple computers later I find I have lost bookmarks over the years.
-FWIW, when I replaced fuel pumps and filter/regulator three years ago they cost me approximately $1000 USD. Plus I had to repair the harness to the fuel pumps due to the dreaded overheating issue damaging the insulation on the wires.

 

Yes it was me that found the febi bilstein filter and posted a guide. I believe someone else had figured out how to open the filter prior and I found the filter.

So I can guarantee that febi bilstein filter fits the E63 and CLS63 filter basket its close enough to identical to the late model e55 one from what I could see. You just have to drill one end out so it fits the recepticle in the filter basket.

So the pulse width modulation is just modulating the 12v feed to the pumps? So my theory should be sound that I can stick any of the mentioned pump in the basket that is brushless and 80psi capable... The issue will be if it provides more pressure at the rail (I dont think it should provided the pump isnt ridiculously massive like a walbro 460lph or something like that because I have read c63 owner doing that and had rail pressure codes). As the filter basket still has the regulator on it so that should handle a slightly bigger pump and I have a wideband I can mount on the car to check fueling.

I have two used w211 E63 pumps here in front of me but I broke the damn quick connect on one while removing from the tank like a retard. So that ruined my "cheap fix".

So now im thinking I'll buy either the aem 320lph or DW300 pumps and stick them in these baskets.


I have heard the oem w211/w219 E63/CLS63 pumps are good to 700-800hp with wiestec superchargers and I know a guy that did exactly that on the stock pumps.

 

I just wanted to confirm something while this thread is up at the top.

2006 e55 - two pumps obviously and two relays, possibly needed some work to ensure no heat in relays - understood.

I wanted to confirm both pumps turn on and off together?

I am working on the system now with many, many modifications and it is return style. I was going to get a one way valve to be safe but it looks like it's both pumps on/off no?

So no need for a check valve/one way since one pump won't be on without the other.

BC

 

Unknown if the pumps operate simultaneously or separately. If it was me, I'd temporarily wire up a pair of LED indicators and run the wires from the relays to the cockpit. At idle, is just one operating or both? I would presume at full throttle both would be operating.
If you could do so, that would be fantastic info to share.

 

I may need to but order of operations with the 10 year build at this point (!) May necessitate me finding out some other way. Need to get this stuff in the tank and at this point I'd need to install the one way now if it's needed. All my own decisions that have the consequences, lol.

 

I finally got around to drawing out a decent three-relay configuration if anyone wants to go this route. See attached. Use at your own risk because I do not know your electrical abilities and you need to decide which gauge wires and fuses to use. The info is out on the internet so feel free to educate yourself if any doubts arise. This is intended to get one most of the way there but you will need to finalize specifications.

 

Sir is this information tied to a 2004 E55? Or is the 2004 fuel pump situation a whole different scenario in itself?

 

This would apply to any 2003 to 2005 W211 E55 or CLS55. This relieves the stress on the fuel pump relay by dividing the current between two relays as was done in the 2006 model year. The 2006 model year, however, uses a different Motor Electronics module that has two separate pins for the two fuel pump relays (versus the single pin and single fuel pump relay on the 2003 to 2005 E55/CLS55).

Myself? On my 2005 E55, I replaced the stock single 40-amp relay with a single 70-amp relay. After 8 years the 70-amp is working well.

 

So I should just swap the 40Amp for a 70Amp? That simple?

My brain is not capable of functioning anything electrical lol 😂

 

A photo showing the difference between 1st/2nd generation filter regulator versus 3rd generation filter/regulator. 1st/2nd gen have a white vapor pressure sensor, 3rd gen has a black vapor pressure sensor which requires an adaptor to connect to the OEM harness.

 

For first timers replacing the fuel pumps, it is a PITA to assemble the pumps inside the tank but it is the only way. Remove top hat, separate and unplug and remove old pumps individually. Next, insert new pumps one at a time, reconnect fuel lines and electrical connectors, then assemble pumps together so the dual metal legs with springs fit into the fittings on the plastic buckets. Install o-ring carefully and ensure it is not crimped or folded. Hold the top hat down against the pressure of the springs while also attempting to install the plastic ring over the threads while not disturbing the o-ring. Tighten the o-ring with the proper tool. Connect power/ground connector to the top hat.
Did I mention it is a PITA?
You want 3 bars and preferably less on the fuel gauge because you are going to be working in a pool of gasoline. I prefer outdoors, no open flames or sparks, and a nearby fire extinguisher.

 

@HemiAlex
The following are the 3rd gen filter/regulator plus the matching 2nd 3rd gen fuel pumps. The prices shown are from 2015; plan on an extra 25% now...

-211-470-00-00 Fuel Delivery Module (dual pumps) $411
-211-470-64-94 Tank Inner Module (actually filter and regulator) $489
-211-471-05-79 Fuel Sender Seal x 2 $34
-211-440-05-07 Cable Harness adaptor for filter/regulator $15
-211-540-07-00 adapter cable to dual fuel pumps $15 (this adapts the fuel pump connection pins 1/2/3/4 from old "+/-/+/-" to new "-/+/+/-")
-203-997-04-81 foam cushion (insulator under metal cover) $1

WARNING: If you do not use the fuel pump adaptor cable, one of the fuel pumps will run backwards. Fuel pressure will drop at wide open throttle and engine damage will occur. Alternatively, swap pins 1 and 2 in the OEM harness but be sure to annotate for future owners! I re-pinned the connector the last time I changed fuel pumps. Photo below.

 

Thank you for all of your help! The new parts to fix my car are on order.

 

A few tips for first-timers. All references are for a left-hand drive car.
-Remove fuel pumps first and install last. Be sure to observe orientation of inboard and outboard fuel pump.
-After disconnecting the fuel and electrical lines from the fuel pumps on the passenger side, remove fuel pumps one at a time.
-Then tie a loop of paracord or similar around all of the lines. 8' or so should be plenty of line. This way, when you pull the filter regulator out of the tank on the driver's side, the paracord will pull through with it.
-Now fasten the loop of paracord around the ends of the new filter/regulator's fuel and electrical lines and, as you are feeding the lines into the driver's side of the tank, you are using the paracord to pull all of the fuel and electrical lines over the saddle and into the passenger side of the tank.
-Filter/regulator assembly just drops in so it is easier. Ensure rubber o-ring is not torn or rolled when installed. Silicon lube may assist.
-Ensure the filter/regulator assembly goes in straight. If rotated clockwise or counter-clockwise, the fuel level float will bind on the side of the tank and you'll have reinstall the filter/regulator assembly over again.

The paracord greatly simplifies the process of getting the fuel and electrical lines over the saddle as arms do not fit very well into the fuel tank.

-Figure out which fuel pump basket goes inboard and which outboard and put approximately in place.
-Connect electrical lines for fuel gauge, connect fuel lines to each pump. Ensure fuel line connectors snap into place and will not pop off under pressure.
-The 00-00 pumps use a "squeeze to release" fuel line connector. (The first gen fuel pumps have a "pull clip to release" fuel line connector.)
-The two return lines only have one plastic bracket to hold a line in place to fill the fuel basket, toss the other line onto the bottom of the tank.

Now the fun part begins...
-Match up the two baskets so the metal rods will fit in and hold in place.
-Install rubber o-rings in fuel tank opening; silicon lube might be of assistance to prevent tearing or rolling. You have to install the plastic o-ring nut while holding pressure down on the top hat (which has the springs pushing up quite strongly). You may notice you now have your hand inside the plastic o-ring holding down the top hat while using your other hand to thread the plastic o-ring onto the threads while simultaneously ensuring the rubber o-ring does not come lose or roll under. Fun, fun, fun!

 

a little back story I have a 2004 E55 with currently upgraded fuel pumps and new filter for about 2 months runs off 2 relays and I've had the car for 6 months. original issue before i owned the car was that the fuel pump fuse kept blowing no one really could pin point the issue not much help forums and groups have told me its the fuel pump so i ended up replacing it and the car was fine for about a week or 2 and fuse blew for the first time with new pump and filter getting onto the highway luckily I had a spare put it in and i was able to drive again for about another week just had spare fuses. fast forward to 3 days ago had a big heat wave in my sitting and it drove fine until i let it idle for about 5min and realized it popped again replaced the fuse it was fine until 2 days ago drove it at night getting off the highway and replacing the fuse kept blowing( i know it was stupid for me to not resolve the issue sooner i was just trying to buy time).

Now looking at the relays one brown and green wire was spliced into brown and blue wire both small gauge wires and the open wire wasn't covered I unspliced it and it worked fine not sure why they did that and then I was able to start it. I found out one relay looking at diagram the original relay (before the update with the second relay) gets really hot, call it relay one (both relays are new) if i switch relays that same relay socket one relay will get hot so I know it isn't the relays for sure. tried to start it up again fuse popped I'm confused running in circles how was it running sort of fine spliced together and unspliced and then just nothing.

relays are fine, no corrosion visible anywhere sometimes car runs sometimes it doesn't under not common condition does it pop the fuse, new relays fuel pump with upgraded wiring on the pumps.

 

hello.

i want to confirm that i am the individual bbirdwell was referencing when he said someone is planning to go forced induction.

whilst i'm still close to the vest on what i'm doing there, i want to confirm that his three-relay approach does work.

because my car had the typical single fuel pump on the passenger side, with the sender/filter/regulator (whatever it is) on the left, i will note the following (this is for an E320 4matic, but i suspect it may generalise to all W211s with this configuration)

• tap the original fuel pump wires (2.5SQ red/grn is power, 2.5SQ brn is ground) that are on the rectangular connector that are on the other side of the SAM.
  • this connector "lines up" behind the fuel pump relay (kA). so you can't miss these wires
• run these wires to two new relays as the power line (so they go hot when the fuel pump relay goes hot and gives power)
• use a maxi fuse with the right connector/wiring to get proper power from the rear pre-fuse box
• follow what bbirdwell says here. the rest is up to you.
  • it seems as simple as running four wires to the rear-passenger side but it will take a bit of time and effort
  • for those adding all of this wiring (as opposed to repairing what exists), i would not recommend this unless you have a lot of experience.
  • you can get hurt. there are a lot of moving parts to this implementation
• have a dremel/cutting tool ready to deal with the lack of an indentation for the wiring on the passenger side fuel pump cap. you will need to make room

 

I’m a bit confused.

I bought the following

211-540-07-00 harness adapter for regulator

211-470-64-94 inner tank module (sending unit and regulator

211-440-05-07 Harness for dual pumps

where it starts to get confusing is this—

2114700000 https://www.autohausaz.com/pn/AH-2114700000

This module is aftermarket and doesn’t match anything I have. I tried to save money and go aftermarket and it bit me. It doesn’t match the module in the car, and the style is completely wrong.


So I left that off the car and used what I had, in the car


I put the 494 module in the car, connected the hoses to the matching fittings, two push in clip onto male fittings, two hoses dumping into the bucket with the hose retainers and plugged up the connector with the blue connector.

I then added the 05-07 long harness for that existing passenger side jumper harness, with the switched polarity and the 07-00 for the regulator adapter.

I snugged both the rings up, reattached the hose with a constant tension one time use clamp and started the car

Within 30 seconds the car started to idle rough and died. I put the fuel pressure gauge onto it and it wasn’t building pressure.

I removed the 05-07 harness, plugged the connector directly to the fuel pump module and restarted. It held 80 psi without issue.

I didn’t drive it or load it up, just idled it with the gauge to see.

I am really confused. Why is this working out like this? Am I doing something right or wrong?

The car is a MY06 and it was built in 10/2005

1st picture is the pump model number, second is the pump with the 07-00 harness in place and Third is the existing module on the passengers side that I hooked up and reused.

 

The best I can figure is that since I don’t have a true 0000 fuel pump on the passengers side I don’t need the jumper harness yet.

I guess I have either a 211 470 17 94 or 211 470 04 594 combo with my 494 pump right now.

Clear as mud to me. I need a beer.