V6 Alternator Replacement

by: b5.5_wagon



Symptoms of issue or other information

First off you're going to need to figure out which alternator you need.. there are 4, yes FOUR different types to choose from.

Options are as follows:

  • 90 amp Bosch system
  • 90 amp Valeo system
  • 120 amp Bosch system
  • 120 amp Valeo system

The 90 amp and 120 amp are NON-INTERCHANGEABLE.
I highly recommend calling a VW dealer and having them check you VIN to verify the system you need.

My 2002 GLX V6 required the 120 amp Bosch system

I would recommend doing this job in stages and placing the nuts and bolts in ziplock bags labeled with what they pertain too.


  • metric socket set
  • screwdrivers
  • ratchets
  • breaker bar
  • torx 20-50


  • 90 AMP or 120 AMP Alternator
  • (4) 1/4" carriage bolts

  • Disconnect the battery.
  • First off you're going to need to remove the front bumper cover. Start by removing the three phillips screws which hold the intake tube on the radiator support.
  • Next up you will need to remove the grill. First remove the two torx 25 screws at the top of the grill on either side. The latch assembly is a little tricky but with a flathead you can push the two tabs apart and the grill should pop out.

Credit to Swankmonkey for providing a little write up in case you need it. http://www.swankmonkey.com/vw/passat...grill_install/

  • Underneath the grill you will find 4 torx 25 screws which will need to be removed
  • Next up you will need to remove the 4 torx 20 screws located on the inner fender wells of each side. Three are on the front of the well horizontally and the fourth is located at the top of fender well vertically.
  • Lastly if they are so equipped, remove the grill inserts for your fogs and then your fogs themselves. 3 phillips screws hold them in. Also removed the bulbs from the back of your turn signal indicators. Don't forget there is one flathead screw underneath that holds the bumper cover.
  • Helps to have a friend but you can by yourself slowly pop the sides out and pull the front bumper cover off
  • At this point your car should look like this and now your ready to move on to putting the car in the "Service Position"
  • Now that your car is here we need to remove the bumper brace. It has 5 Torx 25 that hold it in place. Two on either side at the top where you removed the torx for the grill. Two on either side on the bottom and one in the middle neither the latch assembly. Remove this and place somewhere safe with the rest of your goodies your removed.
  • Now we can go ahead and remove the bumper. Two 17mm bolts hold it on.
  • Now we can go ahead and place the car in the "Service Position". This involves removing 4 bolts on either side of the vehicle which allows the front clip to slide out and forward about 6-8 inches. Before proceeding, Unbolt the power steering oil cooler line and outside temperature sensor from the front of the LC. Also, remove the small retaining clip that secures the temp sensor’s wire. (All this is located and the bottom of the radiator.)
  • I purchased 4 1/4" carriage bolts to use as supports in place of the lock carrier(LC) torx bolts (Torx 45). I removed one LC bolt from the top and one from the bottom diagonal from one another and inserted the 1/4" carriage bolts for support on both sides. Finally your remove the last two bolts and carefully slide the whole front clip forward. You'll feel a little tension from the coolant hoses.
  • Now comes the really fun part!! Using the same 17 mm socket find yourself a breaker bar and relieve the tension on the serpentine belt tensioner and remove the belt out of your way.
  • I found that there is a bracket which holds condensor lines I believe which run right in front of the alternator. getting under the car and removing this will help you.
  • There are two bolts which hold the alternator in place. One is a normal metric and the other is a torx 50. It would be helpful to have a buddy at this stage in the game. He should be underneath the car to brace the alternator. Remove the two bolts and allow the alternator to dip down so you can access the plug which attaches to the back of it. VW put another bolt to something else right above it so it's impossible to snag. Also remove the ground wire from the back of the alternator. I believe its a 8 mm
  • My alternator was very snug in the mount and had to take some shots of PB blaster and persuasion to remove the bad boy.
  • Once you have everything unbolted be prepared to play Houdini as you slide the alternator out being careful not to puncture the radiator.(You could drain the radiator and fluid to remove the whole front clip but who wants to spend and extra $40 on coolant!?)
  • Now it will take a little patience and fenagiling to get the new alternator back in.
  • Once you have it back into place just remember the steps you took to get here and simply reverse.
  • Start car allow battery to charge.
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