Friday, December 28, 2018

SC430 A/C issues and fix.

It was October and with the weather in the low 60's you wouldn't think I would have a problem with the A/C not working but well you kinda need the A/C to defog your windshield and windows. Also I just wanted it fixed. Matt and Taylor at Insomnia Motorsports was kind enough to check on the system. The compressor was not kicking on which could mean low refrigerant, when it was bypassed the compressor was kicking on. We filled up the system with r134a to spec and the compressor was kicking on, as it was supposed to but was not cooling. The pressures in the lines were too high on both the high and low pressure lines which sort of points to a bad expansion valve. Also with the expansion valve being the cheapest part in the system I opted to change that out first. Ordered a new denso expansion valve and swapped it in. Matt connected the A/C recovery, recycle, and recharge machine and pulled a vacuum for about 30 minutes, and verified that there were no leaks etc and filled it back up with r134a refrigerant. A/C was blowing nice cold air again and was on my way.

The expansion valve sits right about the accelerator pedal. Below is a picture of it with some foam insulation removed. The gap between the aluminum blocks is where the expansion valve sits. Below is the picture of the low pressure line that comes out of the compressor that has the muffler on it that I was going to replace. 

It was a week or two later that I drove the car again and well to my annoyance the A/C was not working again. When I checked the pressure in the lines there was pressure so since I had just replaced the expansion valve the probability of that going bad again that quick I thought was slim. The only other thing I could think about was that the compressor was going out. When the compressor goes out or starts to go out it can pump metal shavings through the system and could get caught up in various parts of the system especially the expansion valve which can prevent the expansion valve from working properly. 

So my train of thought was to automatically change every single component in the A/C system. The system consists of Compressor, Condenser, Dryer, Evaporator, Expansion Valve, O'rings and Mufflers and Lines. The only problem was I was not comfortable in taking the whole dash board out to change the evaporator. The Expansion valve even though it sits behind the dash board I could access it without taking the dash board off. So since I didn't see a drop in pressure I ruled out the possibility of a leak which meant the evaporator did not have a leak as well. On the low pressure line there is a muffler on the line connected to the compressor. I believe this muffler is there to catch any metal shavings that might come from the compressor in case it blows up. Also the dryer would catch these shavings as well. Since the evaporator did not have a leak I chose not to change it. Everything else I could access easily and change. 

The only components I wouldn't be changing would be the evaporator and the lines. To clean the evaporator and the lines of any possible shavings I was going to flush the system. Flushing air-conditioning systems is extremely important when repairs are carried out or if a compressor is damaged. The flushing process removes impurities and harmful substances from the air-conditioning circuit. You should not or cannot flush compressors, expansion valves, or filter dryers and mufflers. Use adapters to bridge these components during the flushing process. Once the flushing process is complete, the valves and filters must be replaced. In this method, the air-conditioning system is cleaned with a special flushing liquid (in combination with compressed air).

Below is a picture of the block on the firewall where the lines go into.

I wanted to flush each component separately as much as I could. Flush lines individually and the evaporator individually. The expansion valve is located write behind the firewall under the dash board so without creating a mess inside the car I thought I could remove the lines going into the firewall, leave the expansion valve in place and flush the evaporator out. This would have been great if the expansion valve was on the engine side of the fire wall. Looking at the expansion valve you can see why you cannot really flush through the expansion valve. To provide an easy flow of flush through the system I decided I could take the expansion valve apart. There is a hex screw at the bottom you can remove and you can remove a spring and valve that sits in it. Once that is out I drilled the stem out and made the passages bigger so that it matched size of the lines going in and out of the expansion valve. Put the hex screw back in place and install it back in the car after a thorough cleaning with brake cleaner and forced air. No point adding metal shavings into the system.

Once the modified expansion valve was in place I removed all the components, compressor, condenser, dryer and muffler and flushed the evaporator out. Filled up the flush machine with the cleaner and sprayed it in pulses till the cleaner started coming out from the other port on the firewall. I let the cleaner sit there for about 20 minutes and then used compressed air till all the cleaning liquid flushed out. Then I kept going for another 15 minutes of just compressed air flowing through the evaporator. I capped both the ports shut and continued to flush the lines while I let the cleaner dwell etc. I did that process 4 times and the last time around instead of 15 minutes I did 30 minutes of compressed air just flowing through the system. Make sure you air the system out with the compressed air to ensure all the flush is out of the system. The ideal way is to use nitrogen but I didn't have that. After each line etc is cleaned I capped them off.

The cleaning process I think is what takes the longest amount of time. The removal of all the components are pretty straight forward, well documented and not really time consuming. With all the old parts out I proceeded to reinstall all the new components making sure the lines were capped out so no foreign debris is introduced into the system.

All the new components:

Out with the old:

When replacing the compressor I drained all the PAG 46 oil out of the old compressor and since all the components was new and the lines were flushed out there is no oil in the system. The system calls for 4oz of PAG 46 oil. My thought process was to distribute the oil through the system, put about 3oz of PAG 46 oil in the compressor and 0.5 oz in the evaporator through the lines and 0.5 oz in the condenser. When filling the compressor with oil turn the clutch so that the oil can get distributed into the compressor. I didn't think the compressor could hold 4oz of oil but it took it. I used a syringe to measure the oil so I could be as accurate as I could. 

With everything oiled and cleaned I installed all the new components. Connected all the lines etc with new nitrile  o'rings.

With all the new components replaced and connected I wanted to make sure there are no leaks etc. You can do a vacuum test and make sure there are no leaks under vacuum, however, the AC system runs in excess of 180psi and sometimes under vacuum it might not show leaks but under pressure it can have leaks. The best way to check for leaks under pressure is to actually pressurize the system. To pressurize the system I used Nitrogen. A buddy of mine does HVAC systems for homes etc and that's what he uses to pressurize systems and check for leaks. Thanks Sam. He pressurized the system for me with Nitrogen and verified that the pressure holds even after an hour. 

After verifying that the system has no leaks under pressure I vacuumed the system as well to make sure that there are no leaks under vacuum and vacuum helps get rid of any moisture or other solvents that might still be present in the system. Might be excessive but better safe than sorry.

I let the vacuum run for over an hour and even after three hours the vacuum held with no change in the pressures. 

At this point it is ready to fill with refrigerant. The SC430 AC system calls for between 21 to 23 ounces of  R134a refrigerant. I got the system hooked up to a HVAC refill and recovery machine and had the system refilled. The AC in the car is back to being ice cold, not that I'll be using it anytime soon, but the satisfaction of knowing it is working and hopefully done right keeps my mind at ease. 

Read More

Sunday, August 20, 2017

SC430 Smart Keyless Entry, Push button start and phone control

Since I've had the SC430 I've wanted newer car amenities and smart key and push button start is something I've wanted in this car as well. This is where Advanced keys came into play, when discussing this install with Shaun at 919 Motoring in Raleigh,  NC he suggested integrating the smart key along with a couple of Compustar's components to give it an after market security system and drone which gives me access to features via my smart phone along with GPS tracking etc and no limitation on range.

I did want the push button start in the factory location of where the key was and that I think was the biggest pain in the ass since it was the first one that I had installed. The ignition system once separated from the steering column the rest was just wiring etc. In order to separate the ignition system from the steering wheel column there are two security bolts that need to be drilled out and then removed by dropping the steering wheel column. I did that part and Shaun took care of all the wiring. It's been a couple of months since I've had it on and I'm very happy with it. Car unlocks when I am in proximity to it and locks itself when I'm out of proximity. No keys etc needed to start car etc, trunk can be popped with the new remote. Car can be started via the app on my smart phone along with other features that can be programmed like retract roof, windows down etc. The app also shows the status of the car, doors locked, voltage etc. I'm very happy with it and want to thank Shaun at 919 Motoring for his expertise.

Read More

Tuesday, May 2, 2017

SC430 Audio system planning and upgrade.

I've been meaning to do this write up for awhile but haven't had the time to till recently. I could not have done this without the guidance of 919 Motoring here in Raleigh North Carolina. So hearing a couple of speakers etc I fell in love with the Arc Audio black series. I am by no means an audiophile but these speakers sounded very clean and crisp to me. These are the components I used:

Head unit - Kenwood 9903s
Speakers - Arc Audio Black 6.2
Subwoofer - Black 12V2
Amplifier - XDI 1100.5
Sound deadening - Focal Bam 
Wires - Focal RCA's, speaker wires etc
Trim kit - Beat-Sonic MVA-11FB
Additional wiring harness - Beat-Sonic MVA-13L

I started off by running all the lines and doing the sound dampening with the factory unit still inplace. This is because I did this is stages and worked on the car when I had a chance to so I still had some sort of sound till it was all done. 

Inner and outer door skins dampened

Rear seat were removed and I'm not planning on putting it back in. Wanted to create a more factory looking sub install which I'm hoping it will turn out as I planned once my interior is done. Rear seat area, quarter panel and sides were all dampened as well.

Falls floors setup and then planned out the how the sub should sit. The amp and the crossovers sits under this falls floor. I wanted to keep the rear storage cubby which is why it is open in the pic below to make sure there was enough room for it to articulate open and close. 

Fleeced, resined and fiber added on the inside.

Pretty happy with how it turned out.

On to the head unit. Removed the factory unit and setup the Kenwood 9903S. The unit and brackets were mocked and modified to make sure the door would still close without any hindrances.

Made the speaker pods out of 3/4" poly carbonate and the factory tweeter pods were modified to fit the new arc tweeters. 

Shaun at 919 Motoring pretty much built my box for me and I want to thank him for all his help, guidance and for tuning my system. It sounds awesome and I am very happy with it!! 
Read More

Wednesday, May 18, 2016

C300 Facelift Steering Wheel Swap DIY

This DIY is for those that have a 2008-2011 Mercedes C300 and they want the look of the steering wheel from a 2012-2014 C250/C300 facelift model.

I have a 2009 Mercedes C300 Sport.  I bought a red stitching steering wheel off ebay for $220 shipped.  I got the air bag for it as well off ebay for $250 shipped.  Total cost, $470.

Make sure you get the right air bag, it's very easy to get the wrong airbag, so refer to this thread for details on what steering wheel and air bag to get:

Here's my original steering wheel:

Here's the new steering wheel I got:

To remove the old steering wheel, you can follow the original DIY instructions.   But here's what I did:

1) Disconnect your battery (negative side and make sure it sets aside and can't make contact)
2) Loosen up the two torx screw in the back of the old steering wheel with a T30 torx bit
3) Remove the airbag, it should just pop off after you remove the screws.
4) Then, using a big ratchet or torque wrench, remove the center bolt (I used a 10mm Hex bit that attaches to my ratchet).  You definitely need a lot of leverage, so make sure you have something strong and make sure to not strip that center screw.
5) Take note of where your wheel aligns, make sure to take a picture of it.  Mine doesn't line up perfectly and there's a reason for that.  I messed up the first time around trying to line everything up perfectly, turns out, there was a reason for the offset because my steering wheel was crooked.  I had to pop it off and match it to what the alignment was with the old steering wheel.

Notice how the tick marks don't line up perfectly, it's like that for a reason.

6)  I tried installing the new steering wheel and airbag on hoping that everything will just work.  Needless to say, it didn't work at all, nothing worked.  Buttons, horn, paddle shifter, nothing worked.  So I then realized I have to do a chip swap.  So on with the fun!

*Please note that the chip swap is not a requirement on some models.  On cars like mines, it is required though.

7) The chip swap wasn't too bad, there's just not a lot of information on how to exactly do it, so I am here to help.  The first thing you need to do is take your old air bag, flip it over and remove the 4 screws with a T30 torx bit.

Only remove the four big screws, you don't have to remove the little ones.

8) After you remove the 4 screws, the pressure plate will come off.  Flip it over and you'll see the box that houses the control chip.

There's a bunch of clips that holds the cap on, so you kinda have to pop it off one by one until the cap comes off.

9) Once you get the cap off, you can now see your control chip.  Unhook any plug and you'll end up with this:

10) Now you're ready to take the control chip off the new steering wheel.  The control chip on the new steering wheel is on the steering wheel part and NOT the air bag.

So on the new steering wheel, you'll see a few screws all around it.  First you have to remove the two black screws holding down the chrome bezel with a T20 torx bit.

11)  Then flip the steering wheel over, there's an additional 2 screws on the back.  You can use the T20 torx bit for removing those screws and every other screws from here on out.

12) Once you remove all 4 screws holding down the chrome bezel, you should be able to just pop it off and unhook the two control plugs from it.  There should be a green plug on one side and a black plug on the other.

13) After removing the chrome bezel completely, now you can remove the pressure plate.  There's three screws you'll need to remove and a black screw holding down the brown ground wire.

14) After you removed the pressure plate, you'll see a black plastic piece.  Pop this off, behind it is the new control chip.

15) Remove the cap and you'll see the new control chip:

remove this chip:

16) Now, you can see the difference between the new chip and old chip.
Make note of how the big brown plug is connected to the new chip, but there's no brown plug on the old chip.

17) You need to go back to the old air bag and remove the brown plug from it:

18)  Connect the black plug on the other end of the big brown plug to your old control chip:

Make note of how it should connect back.  There's numbering on there.  This picture shows you how to hook it up:

19) Now there's two plugs on the old chip with yellow wires.  You'll need to hack these plugs up a little bit in order to get your horn to work.  The first thing you need to do is get a little super thin flat head screwdriver and push down on the metal pieces on the opening of the plug:

After you push it down on one side, flip the plug over and push down on the metal on the center opening on the other side as well.

If done correctly, the plug will just slide off and look like this:

20) After you remove the yellow wires from the plug, here's what you can do to avoid having to do any soldering.  Take a needle nose plier and flatten the metal ends like this:

You should end up with these flaps.  Just cut the flaps off with some wire cutters.

21) Once you cut off the flaps, you can take the needle nose plier and crimp the metal ends in half to make it look like this:

22)  Make sure each of your yellow wires with the modified ends can plug into this slot here:

23) Now you wire up the yellow wires like so:

24) After you hook up the yellow wires, fold them over 90 degrees and make sure they don't touch each other.  I put electrical tape over them to make sure they stayed in place.

25) Now, plug the control chip into the black plastic backing piece.  I popped off some of the paddle shifter wiring to make sure it connects to my control chip, but I douldn't figure out how to get the paddle shifters working, so I gave up.  Maybe someone can figure this out later.

I ended up using more electrical tape to cover the control chip because the cap won't fit back on.  It's not a big deal since you'll pin it between the steering wheel once you screw it down anyways:

26) After that, you can re-assemble everything back.  Put the black plastic piece back on the steering wheel and assemble it with the pressure plate.  Make sure you run all the plugs and wires through the middle.  You don't want any wires between the pressure plate because you need it to spring up and down for the horn to work.  And don't forget to screw the brown ground wire back on as well.

27)  Now you're ready to put the chrome bezel back.  The two black plugs will need to be plugged back.  Please make sure that you plug the black plugs back into the right spot.  These plugs have to criss cross each other when you connect them.  I made the mistake of not doing this, and none of the controls worked.

Also note that one side will plug right in, while the other side, you'll have to cut off the bump on it to make it plug in.

28) Lastly, put everything back and test out to see if everything works.  Make sure you disconnect the battery each time before you remove the air bag.  Also, don't tighten everything down until you make sure that your wiring works.

29) Pro-tip, make sure you tighten the negative on your car battery very well before turning on your car to test the steering wheel.  I made the mistake of not tightening it well and thought my battery died lol.  Just kidding, this is not a pro-tip, I was just not thinking straight.

The End:

Read More