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This article details the steps required to remove and replace the EBCM on a 2001 Z06. There are numerous Corvette Forums where owners who have performed this repair have uploaded their procedures and photos. You can refer to them via the links section below for other ways of doing this.
I cannot emphasize enough the need to be gentle when removing this unit (if, as I did, you intend to have it rebuilt: see below) since it contains an electronic circuit board with microprocessors and a weather seal between the EBCM and the BPVM which you must not damage. Also, the wire connectors which must be removed have specific procedures for removal which if not done properly will damage the connector.
The only tool required is a #20 Torx screwdriver, although a 1/4-inch drive ratchet with a #20 Torx bit attached is a big help for some of the screws that need to be removed/replaced. You can jack the car up as I did to make things easier. I have read where at least one other owner believes this is not necessary but I found it much easier to remove the lower screws with the front of the car elevated. If you do jack it up you will need a floor jack and two jack stands to safely support the car.
Before you do anything, clear the DTC code C1214C (or C1214H "H" for history, if you hit the "reset" key on the DIC to clear the warning messages) so that there will be no trouble code present when you start. This is necessary so that when you finish and turn the ignition on there will be no stored codes to cause confusion. Once you start work do not turn the ignition switch on since a lot of codes will be set with the EBCM disconnected.
You can begin the procedure by first locating the EBCM which is mated to the BPMV (Brake Pressure Modulator Valve) assembly just ahead of the alternator on the driver's side of the car. See photo. Notice that two hoses block the view. Some sources recommend removing the radiator hose, as well as the air bridge. The shop manual recommends removing the insulator nuts and insulator bolt to move the entire unit up. However that does not give you much more room to work and requires replacing the insulator nuts with new ones (which your dealer will have to special order slowing the job). The hoses are pliable and can actually be moved left or right when accessing the EBCM to I choose to perform the work without removing anything.
Here is a view of the EBCM with the hoses pulled toward the front of the car. You can see the label which contains the part number, as well as the serial number of the unit. Notice in this photo the latch which must be gently pried up to allow the connector to slide off and the connector release lever above it. That lever needs to be pulled up to release the connector. Then you must cut the white plastic safety strap which prevents the connector from sliding out. You can replace this with a cable tie when reinstalling (or order the real thing from the Chevy dealer). Do NOT cut the other end of this strap which has a loop circling the grey wire in the wiring bundle for this connector. You will reuse this loop to attach one end of your cable tie when reinstalling the EBCM. Noto Bene: I followed the instructions to CUT the safety strap and replace it with a tie wrap. Another owner's site suggests that the strap simply pulls out and does not need to be cut. Grrrr. To be fair, I pulled on it to see just how hard a pull was required, even using pliers, but it would not bulge. So maybe using the wire tie solution will work better.
There are two connectors to the EBCM. A large one and a small one as seen here in a shot from beneath the car. The photo contains labels to make identication easier. Do not remove the screws indicated by the "Do NOT remove" labels. These screws hold the cover on the EBCM. The screws marked "#20 Torx Screws" are the ones to remove and there are six of them. One screw is at each corner of the EBCM, and there are two located in recessed slots on each side of the unit in the sides at the middle. These are the most difficult to remove/replace. This photo also shows the safety strap end which circles the grey wire in the bundle.
In order to show the location of the top safety strap it was necessary to photograph the unit dismounted. In this photo you can clearly see the slot where the safety strap will be located and where you must reinstall the factory strap or a tie wrap (if you cut the OEM piece) when reinstalling the unit. This photo shows the other end of the strap with the top connector disconnected. To disconnect the top connector, pull the release handle up and slide a thin screwdriver in the gap between the connector base and the EBCM. It does not take much pressure to ease it off.
The bottom connector can be removed by GENTLY pring up the connector latch with a pick. This connector then slides out easily.
Remove all six #20 Torx screws, being careful not to drop any since they WILL fall into an area where they are very difficult to retrieve (trust me on this). With the screws out, GENTLY use a thin screwdriver blade to ease the EBCM away from the BPMV assembly. You must NOT damage the rubber seal that fits between the EBCM and the BPMV. Pull the EBCM straight off the BPMV as there are 12 pins the unit slides off of. Removal of the EBCM is best done from undrneath the vehicle since there is adequate clearance there.
There have been assertions by some owners that the vehicle can be driven with the EBCM off since you'll get the same warning displays as you would with the defective one mounted and still have brakes (although the DRP or Dynamic Rear Proportioning will be diminished). I don't advise this unless you have no alternative since dirt and moisture can enter the BPMV and connectors, even when covered with plastic (which I strongly recommend even if the car will remain in the garage until the rebuilt EBCM arrives for reinstalltion).
Following are some photos of the EBCM after removal and included here to facilitate identification and location of components. The first photo shows the connector side of the EBCM. The locations of the screws to be removed are labeled, as are the locations of the screws you should not remove. Clearly visible are the two connectors and the top connector release handle (in the release position). The actuator side has the seal which mates with the BPMV. Take care not to damage this seal when removing/installing the EBCM. This photo is from the side of the unit viewed from the front of the car with the release handle in the release position. This is the same view but with the release handle in the lock position.
Once you have the unit removed you have three choices: 1) Buy a new unit from your Chevy dealer ($1,300) ; 2) Buy one from an on-line distributor such as GM Parts Direct ($695); 3) Send the unit to Brandon Hite at absfixer.com and have the solenoid in your unit replaced for $150 plus return shipping (costs of shipping ranges from $60 for UPS Next Day Air, to $8.00 for UPS Ground with plenty of options in between). I chose to send the unit to Brandon, who offers a guarantee on the unit for as long as you own the car.
Given that with parts and labor at the Chevy dealer approaching $1,700 in total it makes sense to replace the unit yourself. Whether you buy a new part from Chevy or a distributor you will still have to pay anywhere from $695 to $1,300 just for the part. Sending the unit in for rebuild will cost you $150 plus the return shipping of your choice, and the cost of sending the unit to Brandon in Missouri. Even sending it to him at $60 for UPS Next Day Air leaves you having saved a substantial amount of money. Plus doing it yourself gives you sweat equity in the car and the satisfaction of doing it yourself.
The web site for Brandon Hite's business is http://www.absfixer.com/. At Brandon's site you will find instructions for removing the EBCM and a form to fill out to send in with your unit. You can pay by credit card or Paypal. I sent mine to Brandon on a Monday via UPS Next Day Air and specified UPS Second Day Air return shipping. I received the rebult EBCM on Friday and installed it immediately. The turn-around was fantastic.
Here is a photo of the label on my EBCM. Note that part # 10315150 (which is a 2002 part but was installed on my Z06 because it was a June 2001 build) has been superseded by GM part #1221656. Early build 2001 cars had a part number #12208997.
Unless you have to drive the car, do NOT turn the ignition to "ON" while the EBCM is missing as it will only cause the system to set a code C1214C again.
Reinstallion of the EBCM is the reverse of the removal procedure. Before mating the EBCM to the BPMV, clean the seal between the two with rubbing alcohol. Gently place the EBCM over the pins on the BPMV and push until snug. Then begin replacing the #20 Torx screws, which is a tediuos and time consuming procedure. Once all screws have been snugged up, they should be torqued in two stages: 1st to 27 inch-pounds, and then to 53 inch-pounds. Be very careful when installing these as stripping the head of even one can lead to a very expensive repair bill. Don't even think of using a GrabIt since there is no clearance for a drill once the unit is mounted.
Installing the two middle screws is very difficult, since they have a tendency to slip into a groove in the EBCM. You will think you dropped the screw but it's actually lodged on the little shelf formed where the EBCM goes under the BPMV. A magnetic retrieval tool can help here.
Once the EBCM is installed reconnect the bottom and top connectors (in that sequence). The top connector must have the release handle in the down position and then have a wire tie (or the genuine GM part) installed to prevent the connector from vibrating loose.
At this point start the car. You should have cleared any codes that were set. If there is a history code (DTC C1214H, the "H" means history) clear it. If you get a "current" code of C1214C something is wrong. Recheck the connections.
After reinstalling the EBCM I drove the car over two hundred miles and no codes have reappeared.
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