Remote Parking Brake Release conversion for 2003 300B & 2004 300A
Parts list:
3W1Z-2780-AA Parking Brake Control Assembly, List $51.75 (You only need the vacuum cylinder and bushing-see photos)
F5OZ-2B623-AA Shifter Switch Assembly, List $19.20 (This may already be on your shifter-see photos)
1W3Z-2B653-AA Switch Assembly Vacuum Hose From Shifter to Brake Control, List $18.73
1W7Z-19C827-AA Switch Assembly Vacuum Hose From Engine to Shifter & EATC, List $17.77 (optional, This requires a lot to put in, see narrative for choices)
The best time to do this is when you also do the electric remote fuel door conversion as you have to take off the same parts to get to both.
First a few things to check.
Remove the driver’s side kick panel, and the black plastic cover that holds the interior light.
Pull the cover off the console top per the shop manual. If you don’t have one, gently pry up on the console tray and door assembly. Then remove the center gauge pod by pulling slightly down and rear. Move this off to the driver’s side for clearance. It’s a tight fit, so take your time. Then lift up the console top from around the shifter. You should end up with what the shifter picture looks like. Look inside and see if you have a white plastic assembly on the passenger side of the shifter. It has two staggered vacuum ears pointing toward the front of the car. Look at the picture and you can just see it inside the console. It should be there as the shifter is serviced as an assembly for cars with and without the brake release. If it’s NOT there, you need to order the F5OZ part above.
Next thing to check is your existing parking brake assembly. Look at the picture with the two fingers pointing out two brackets on the inboard side. I tried to take the picture to show what it would look like from the foot well. You should have the two brackets. If not, you have a lot of taking apart to get to the whole parking brake control out. It involves removing the PCM, wiring connecters, and the left side of the dash. It’s too involved to repeat here, so you need a shop manual for reference. You should be in luck, as the assembly should have the brackets.
Last, look at the vacuum hose coming through the firewall just above and to the passenger side of the gas pedal. You will see a large black grommet with a small black hose and a larger white hose next to it. Your white hose should end a few inches inside the car from the grommet. I took a photo of the hose assembly removed to show what you should see. If this is here, there is a shortcut to the install you may want to use to save a lot of time and disassembly.
Let’s get started.
Run the two hose ends of the all black hose assembly into the driver’s side of the front of the console over to the passenger side of the shifter. It can just lay on top of or under the shifter cables. The plug end will only go on one way on the white plastic shifter switch nipples. After that you can reassemble the console. One end of the black hose should be just outside the driver’s front of the console. The other end has to be run up over to the brake assembly. In 300A’s it runs up behind the dash between the lighting control module (large black box behind dash in line with gas pedal) and the console. Looking up inside the dash from the foot well there is a large harness that runs across the top of the dash. The vacuum hose runs along this harness over to the outboard side of the dash. You should see a solid black cable that runs down that side too, this is the shifter cable. The vacuum hose has two clips that attach to the shifter cable, one on the inboard side near the LCM, and the other on the outboard side to the shifter cable near the driver’s side kick panel. If you have it run right, the rubber plug will be just above the forward (close to front of car) bracket of the parking brake control. Next, on the new brake control assembly, carefully lift the plastic retaining clip off the vacuum bellows. It’s a grey plastic 2" drum looking thing. Once you have that end off, lift it perpendicular to the brake control, and the front ear should come out of the other lever. There is a small white plastic grommet in this lever hole you need to transfer to the one in your car. Then install the bellows the same way it came off the other brake assembly. It should just snap into place on the bracket. Then plug the vacuum hose end on and your 90% done. You have to buy the whole brake assembly just to get the vacuum bellows and grommet as they are not serviced separate.
Now you have a choice, if you are anal like me and want it to look like the factory did it (correctly), you have to remove the front center dash trim panel and EATC control head if you want to install the factory vacuum harness assembly. The trim panel has two screws holding it on from under the dash, so you have to remove the panel under the steering wheel and the glove box. The panel snaps out, and the EATC control comes off with four screws. You can lay it off to the side. Protect it with a shop towel. The shortcut is to just run a piece of 1/4" vacuum hose from the existing cut end coming out of the firewall to the black end that is next to the front driver’s side of the console. Then working under the hood, look at the center rear behind the engine. You will see a vacuum tree on the firewall. The very bottom nipple has a plug on it. Remove this plug. About an inch away to the driver’s side you will see the other end of the white tube, it has a yellow plug in the end. Remove the plug and plug the tube into the vacuum nipple and you’re done!
You may find that the white hose is a few inches too short to reach the vacuum nipple. If that is true, you can slide more of the white hose through the grommet from the interior side to reach.
Since the engine vacuum harness is only $20.00, you can order it and then cut off the inside portion of the white tube and connect it with a short piece of hose to the existing hose. This will save about an hour of extra work.
If you don’t have that piece of white tubing already in the car, you have to change the entire hose assembly. It’s not that hard, but you have to remove the white rubber hose from the passenger side air door after the under dash trim panel is removed. Before you pull it out attach a piece of soft coat hanger to be able to pull the new one back through (it runs up and over top of the A/C ducting assembly behind the dash. The hose assembly has a big white junction block that hooks up to the end coming from the EATC control. The hoses are color coded. You can change them out by working through the EATC control opening. This is good task for Mrs. Wrench as small hands are a big plus. Follow the old way the hoses are routed and clipped in place. I would recommend that you just cut the new hose assembly and splice it to the existing one if you aren’t familiar with taking the dash apart, plus you run the risk of ending up with a dash rattle when you take these dashes apart.
To test, apply the parking brake, start the engine and shift into drive. It should release in about a second or less. If you have to go into second gear to make it release, the shifter switch has to be adjusted. This is done by loosening the two screws on the switch and moving it until the brake releases in D. You shouldn’t have to do this as the vacuum switch is usually adjusted when the shifter is manufactured as they don’t know what car it is going to end up in.
Good luck, and as always, E-mail any questions.
I have this in WordPerfect too if anyone needs it E-mailed to them.