Mercedes Benz S600 Coil Pack -   Ignition Coil Repair for Ignition Control Pack/Module - All V12 Engines 2000 - 2012 

Is your Mercedes V12 running on less than 12 cylinders ?  Disgusted with the idea of spending $1,400 for a new coil pack? Finally, a cost effective solution exists to get your V12 back to 100% !  We've all been told the ignition control module is a sealed unit, a black box with no serviceable parts inside.  I have had my S600 for over ten years and suddenly the car lost power, performance and driveability.  I've combined my 25 years of electronic manufacturing experience in Silicon Valley with my dysfunctional Mercedes S600.  The result was a cost effective solution that I want to share with the world !


At V12icpack we can replace the coils and MOSFET transistors controlling a single cylinder for as little as $275 or rebuild your module for as little as $699.  No longer do you need to put off getting your V12 Mercedes running like it should - a 12 cylinder beast !



Our technicians are highly trained electronics professionals.  We have the tools, knowledge and equipment to test and repair your ignition coil module. All modules will be tested before work begins to ensure which cylinders are misfiring.  Unfortunately, no two coil packs ever seem be the same failure mode.  From an engineering standpoint, we have been able to identify critical components within the printed circuit board's circuitry. From this critical standpoint we are able to pinpoint defetive MOSFET transistors, diodes, capacitors and zener diodes that have rendered your coil pack useless.  The ability to pinpoint failed components is what sets us apart.

Quality of Workmanship

What do I do now ?

Its a horrible feeling when the check engine light comes on your dash.  If you have engine misfires the first code that typically comes up is P0300. This is a generic failure code simply indicating, at a summary level, that there is a misfire.  From there, the reader, for example will indicate P0302 and P0304.  The last two digits correspond to the cylinder number, so in this case, the 02 and 04 correspond to cylinders 2 and 4.  When sitting in the car, the left side is the drivers side (except for the UK - where the left side is still the left side but not the drivers side) and the right side is the passenger side.  The passenger or right side of the engine are cylinders 1-6 and the left side, or driver's side are cylinders 7-12.  If you don't know when the spark plugs were last replaced, change the spark plugs with the direct OEM replacements (see below) and see if the misfires go away.  Generally, new plugs will cause 50% of the misfires to go away.  The car will still run horribly with just one cylinder misfiring so you're now going to have to deal with the coil pack.


We do not recommend fixing or repairing just one or two cylinders.  It won't hurt anything to do a partial repair but the likelyhood of other cylinders misfiring in the very near future is very high.  The cost of double shipping and double labor will prove to be very costly.  The exception to this would be physical damage to the pack when it was working perfectly (having a coil break out when pulling out the coil pack, accidently dropping or stepping on it while changing the plugs).  If your getting failure codes on all six cylinders from one side it may not be your coil pack........ the OBD readers/codes cannot tell a coil pack failure from a Voltage Transformer/Ignition Control Unit failure.  The voltage transformer/ignition control unit is a multi level output voltage transformer unit converting 12 volts to 23v and 180v.  In simple terms you can think of it as a power supply for the coil packs. The unit is literally built in two exact halves that make up the whole unit.  Each half controls the power output to one coil pack.  A defective VT/ICU generally kills an entire pack (cylinders 1-6 or 7-12) and maybe 2% of the time can effect a single cylinder. The VT/ICU is located on top of the engine, in the middle, towards the front of the car


Because it is nearly impossible to tell a coil pack failure and a VT/ICU failure we offer both of these units as rental/test assemblies.  If the rental unit resolves your problem you can leave it in your car and purchase it.  If it does not fix your problem, simply return it and pay the very reasonable rental fee.  All coil packs used for rental purposes are completely rebuilt, as new units and carry a one year unlimited miles warranty.  The VT/ICU's have all been upgraded with higher temperature rated components and also carry a 1 year unlimited miles warranty

Watch this video to get an understanding of what's going on out in the market place.  I show how the coil packs work as well as define why the packs fail and introduce our coil that is being produced in our own joint venture captive manufacturing facility.

Thank you World for supporting our efforts !

DIY videos

The ignition coil pack video below shows what's involved in removing the module from an S600. It also goes into some detail about what is inside the module.  Hopefully, by seeing what's inside, you'll be in a position to decide if this is a task your skills will or will not allow you to accomplish.  If you're going to send your module in for repairs, please don't try to open up the cover and risk damaging it.  We are unable to get replacements.

Power connector to coil module (disconnect)

OBD failures P0300, P0301-P0312 misfires - some diagnosis ideas

This video goes through some scenarios that may help you identify or eliminate potential issues.  If you are experiencing specific misfires on less than one entire bank i.e., fewer than six cylinders, you cannot necessarily rule out a voltage transformer failure but it is highly unlikey. If you don't know when the spark plugs were changed last or it has been more than 30,000 miles, start your diagnosis by replacing all the spark plugs (or at a minimum those cylinders showing a misfire).  Normally aspirated V12's call out a double platinum plug (platinum center electrode and platinum ground electrode) but twin turbo V12's must use iridium plugs.  Iridium is a harder element than platinum and holds up better and takes less energy to fire under the higher boost pressure of the TT's. Double platinum plugs with a standard diameter core in a turbo V12 may cause the ignition coils and possibly the voltage transformer to fail. Worn spark plugs, plugs with too large of an air gap (center electrode to ground electrode) will cause the ignition coils to fail - the question is whether or not the failure is permanent or not.  You can use iridium plugs with all V12's they cost a bit more though.  Do your homework on the plugs you want/need.  Some plugs are rated with a service life of only 30,000 miles.  Others go up to 120,000 miles.  After replacing the spark plugs inspect the spark plug boots (see Youtube video below) and reinstall the coil pack.  Reset your engine codes, restart the engine and see if your situation has improved  (you'll probably have to drive it to put a load on the engine).  If you call your local MBz dealer, or go on line with your VIN you can get your engine model number which will call out the MBz spark plug part number for your vehicle.  From there you'll have to cross from the MBz part number to the OEM.  For example, a 2001 S600 that has engine 137.970 uses a MBz spark plug p/n 004-159-07-03 which was made for Mercedes by Beru with their spark plug 14F-7DPURX2. From there you can cross to other manufacturers and see what's available.  In this case, it crosses to a Bosch FR7KPP33U.  The twin turbo models from 2003 -2016 all used NGK brand spark plugs as the OEM plugs.  They are iridium plugs and the NGK number is 1FR6Q.



The technical explanation of what we see happening


When the electrode wear increases, the resistance in the spark gap increases causing the current to go down. Excess voltage cannot develop in this circuit due to the drop in current.  Additionally, the voltage transformer is voltage limited, in terms of voltage output.  Most coil failures we see are due to a high resistance and not shorting out.  In essence, over time, these coils are subject to heat, electricity and vibration.  Any tiny resistance will eventually become a larger resistance.  The higher the resistance, the more power the coil dissipates in the form of heat (P=I*I*R).  this problem cascades until the coil completely burns out (goes open/infinite resistance).  When someone replaces their old plugs, more current flows across the arc gap because there is no longer as much resistance.  When that larger current flow goes through an old, worn coil even more heat is dissipated - damaging the coil even further.  Same with a performance tune, the increased spark duration (more current run time), which will result in burning up the old coil even faster.  Old plugs will make your coils last longer, but your performance will suffer - right to the point of spark plug or coil failure.  For these reasons, it is not uncommon for a coil pack to experience more cylinders reading a misfire after changing the spark plugs or after a performance tune is downloaded into the ECU.


As shown in the failed coil video below we are also see a failure in the plastic tube housing.  The secondary coil is putting out more than 60,000 volts and the plastic tube (inside the metal tube) is the insulator.  We've seen multiple coils develop a small crack in the plastic and of course its arcs/grounds out on the metal tube.  This type of failure will definitely trigger a misfire code. The misfire code is the end final result of what has transpired through the ignition cycle.  There are lots of variables and possibilities of what can go wrong...... A short to ground through the coil can ruin several components on the printed circuit board.   The MOSFET transistors on the coil packs act as electronic switches turning the spark plugs on and off.  They can handle up to 1,700 volts at 4 amps which is pretty considerable considering their small size.  Each spark plug has its on controlling MOSFET.  There is a secondary set of MOSFET's and these act as master switches for both the A and B channels of the ignition circuit and work in pairs on three cylinders (1-3, 4-6, 7-9 and 10-12).  These parts can fail by simply becoming dysfunctional.  They can also fail from getting fried as the result of a direct short at the coils which will draw too much power from the VT/ICU.  The VT/ICU can generate as much as 10 amps output which can totally overwhelm the 4 amp capacity of the MOSFET's controlling the ignition coils. Not only can this power surge destroy the MOSFET transistors but will also blow out diodes and zener diodes that are in the ignition circuit. This is why its so important that the people rebuilding your coil pack clearly understand what's involved in troubleshooting and resolving all of your pack's potential problems.



The Voltage Transformer

The voltage transformer sits in the middle of the engine underneath the V12 emblem/engine cover.  The voltage transformer or ignition control unit is essentially the power supply for the coil packs.  The unit is litterally two independent halves operating as one unit.  If you are receiving OBD codes P0301 through P0306 or P0307 - P0312 there is a 50/50 chance its the voltage transformer and not the coil pack or said another way........there's a 50/50 chance its the coil pack and not the VT.  The codes and the way the parts fail are identical as reported by the ECU, which means its impossible to tell which one has failed. In some cases a faulty VT can trip a single cylinder error code which makes the diagnosis much more frustrating !


Here's the really cool part.....


Mercedes allowed the VT's to be built with consumer grade components.  For this reason they recommend replacing these units between 60K and 75K miles.  They know the engine heat is going to cause them to fail. What we are doing is replacing all the high voltage components with automotive grade parts - this alone will increase the reliability.  Additionally, we are stripping out a series of electolytic capacitors that are subject to leaking electrolyte (acid) on to the the printed circuit boards and replacing them with solid state tantalum capacitors - again increasing the reliability.  Lastly, but more importantly, we have added fuses internally into the units.  These fuses will protect the VT's from being destroyed by a failing or failed/shorted coil pack.  At this point our rebuilt voltage transformers are superior to what you can buy at your local Mercedes dealership and we'll offer the same two year warranty ! Please watch the video below for a clearer and more through discussion about the VT, how it works and what we've done to make it a better and more resiliant component.


Rental program for Voltage transformer testing

It can be really hard to be 100% certain you've diagnosed the difference between a failed coil pack and a bad voltage transformer.  In either case, its a $700 venture and its important to get it right !  It is now possible, through this website, to rent a voltage transformer for just $50.  You can test with it for up to ten days and then it must be returned or purchased as a used component.  If the rental unit fixes your problem, you can keep it and the rental fee will be credited back to you.  If you elect to purchase a new one, or the voltage transformer was not the problem, you can simply return it and the deposit fee and the $100 core fee will be credited back to your account.  It just doesn't get any simpler.  Be sure to watch the video below about installation concerns and procedures. These units are 100% functionally tested before being sent out and after being returned to ensure performance integrity.

Rental program for ignition coil packs

We also have coil packs that can be rented for test purposes.  Similar to the voltage transformer program, if the rental coil pack fixes your problem you can elect to purchase it.  Every coil pack that goes out as a rental has been recently rebuilt and  in-car tested to ensure 100% functionality.  The store check out process is a little more involved......You will need to check the correct rental box for right side (passenger -  cylinders 1-6) or left side (driver - cylinders 7-12).  The deposit box must also be checked.  The deposit fee is the same amount as the full rebuilding charge of $699.  Finally, the core charge box must also be checked.  If you rent a coil pack and return it, your deposit of $699 and the core charge fee of $300 will be credited back.  If you decide to keep the rental unit, the rental fee of $90 will be immediately credited back to you.  When your core is received at V12icpack we will credit the $300 core charge back to your account.  Please note !  If you have tampered with your coil pack and cracked or broken the cover we cannot accept it as a core i.e., you cannot participate in the rent to own option.  If you have broken your cover and rented a unit which fixed your problem, you will need to return the rental unit and send in your coil pack for a rebuild.  You will get your unit with the damaged cover back.  Please call or email before placing your rental order to ensure we have product availability.  As a side note, we are willing to buy defective coil packs. If you have old ones sitting around and want to convert them to cash please let us know !

What models and years can be repaired ?

The modules that we can currently repair are for production years 2001 - 2017. The actual models covered are the CL600, CL65 AMG, S600, S65 AMG, SL600 and SL65 AMG.  As a double check, the actual ignition coil should be stamped on the metal guide tube with "BERU 0040103003" and "TEMIC 288 676".


Valve cover gasket and intake manifold gaskets for non-turbo

As complicated as the turbo units look, replacing the valve cover gaskets on the normally aspirated, non-turbo units is actually far more labor intensive..... production years 2000 - 2002.  Based on the 100's of coil packs that have come in, close to half of them have come off cars with significant oil leaks.  With either model the coil packs have to come off to get to the valve covers so if yours is leaking you may want to take on this task while you're there.  Chances are very high if you have oil around the bottom of the ignition coils, that is oil that has weeped past the valve cover gaskets, run down the cylinder head and collected in the spark plug wells.  If you've noticed a fair amount of fresh oil be sure to clean out the spark plug well before removing the spark plugs.  I now carry OEM quality valve cover gaskets and intake manifold gaskets in my store that are available for same day shipping at better pricing than your local MBz dealer.

Fuel rail and fuel injectors       Non-turbo models 2000 - 2002

The fuel rail on the non-turbo engines needs to be removed in order to remove/replace the fuel injectors.  Fuel injectors can become clogged to the extent they cannot spray a sufficient amount of fuel into the cylinders under high load situations.  The can also get "crud" stuck in the body of the injectors that will prevent them from completely sealing when shut off.  There are several additives on the market that can be added to your fuel system that can help clean/keep clean your fuel injectors.  I'm a huge fan of "Sea Foam" and that can be purchased at most automotive stores and big box stores with automotive sections.  In the event you have a defective fuel injector you can typically get thoses too, at your local auto supplier.  Signs of clogged or stuck injectors could create a sluggish or loss of horsepower feel.  They can create a fuel trim error code of they are not closing and allow fuel to entire the combustion chamber at all times (too rich).  While the injectors can be a bit of a nuisance to get to they can be interchanged if you are have an misfire issue that seems to always stay with just one cylinder.  Swapping injectors from one cylinder to another and seeing if the problem goes with it is one way to determine a faulty injector that is not fatal.  The video below goes through the removal/replacement process.

Fix my module !  What's the process ?

Step 1.  Determine which cylinders are not firing (reminder... cylinders 1-6 are on the right, passenger side.  

             Cylinders 7-12 are on the left, drivers side.  Remove the appropriate IC module(s).

Step 2.  Pack the module(s) very carefully !  Include a note indicating which cylinder(s) are bad.  Include the 

             best way to contact you should we not find the same failure mode.

Step 3.  Billing will occur in two cycles.  When shipping in your module(s) drag the appropriate 1 module or                    2 module item into the bag.  Your card will be charged the $10 or $20 initial item processing fee.  This                fee will be applied to the total repair charges in the table above. When the module has been repaired                  we will contact you to process the balance due payment.  *NOTE - the pricing structure is based on                    coils replaced per module.  

Step 4.  Take your package to your shipper of choice and send it to us.


Note 1. The payment page is a little confusing....The button makes it look like PayPal or phone orders are the                  only two options.  Leave the PayPal button "on" - the next page will ask for Visa or MC choices and                      account number information.  We don't accept phone orders. (Sorry this payment page cannot be                      changed by the website builder).

Note 2.  All modules will be returned priority mail through the USPS.  If you want your module(s) returned                      quicker, note that on your order form for what returned postal service you would prefer. Your credit                    card will be charged accordingly.  International, Alaska and Hawaii customers will be advised of return                shipping charges.

Note 3.   There will be $75 charge for testing and returning modules that are found to be trouble free - plus


Just the coils please.....

If you have watched the YouTube video that explains what is under the module cover and you think you're up for the task, you can order the ignition coils directly from us.  Each coil set will be sold with the matching set of MOSFET IC drivers.  You may order a single coil but the MOSFET IC's will not be included.


Let's talk about something else...

Maintenance on these cars is critical.  It sometimes seems like we can just keep driving until there is a problem. Fuel filters are one of those things that often get overlooked.  There is a wide opinion of how often these should be changed.  If your car has between 75,000 and 100,000 miles since it was last done - its time.  the following video shows where it is located - pretty simple task but you'll have to twist off hose clamps and replace with conventional screw closing hose clamps

Before any rebuilt coil pack ships out

Click on the V12 logo below to enter the store for processing your rebuild order

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