Owning a 97 A8, I really wanted to have Tiptronic after I purchased my car. Thinking that it was almost impossible, I had researched putting a six speed manual transmission in the car from Europe. While studying all the wiring diagrams, it was determined that the wiring diagrams for the 97, 98 and 99 were all the same. They all showed the tiptronic controls in the schematics. So I researched the project and determined that the transmission control unit (TCU) was already wired for the tiptronic controls.
The following article is a step-by-step procedure to retrofit tiptronic controls to a 1997 A8. This is not a difficult task, but it's not easy. This article gives you all the information that you will need. However, if you don't know how to read a schematic or don't understand how electricity works, there is a possibility of doing something wrong. If attempting to do this upgrade, please study this procedure in detail multiple times before attempting.
Special Tools Required
- Pro-Fit hook tool set (qty 2 180 degree tools)
- Pro-Fit dash trim removal tool
- Soldering iron, solder, heat shrink tubing (or a crimping tool and the correct lugs)
- Complete Tiptronic shifter from a 1998 or 1999 parts car
- RJ-45 computer network cable
Used tiptronic shifter. This should cost about $150 - $250 from a parts recycler.
Running the RJ-45 Cable
Three wires will need to be run from the transmission control unit which is located in the electronics box under the hood to the tiptronic shifter in the console. To accomplish this, a RJ-45 computer network cable is run. It has eight conductors, only three will be used.
The cable will be passed through the firewall to the electronics box from the passenger compartment. This is accomplished by fishing a hanger from the electronics box to passenger compartment, attaching the RJ-45 cable to it and pulling it through.
First remove the passenger side floor mat and carpet. You won't have to remove the console side panel until you are ready to install the new shifter assembly. Remove the four screws on the relay panel cover. This is the pressboard plate on the forward section of the passenger footwell.
Open the hood of the car and open the electronics box. The electronic box has phillips head screws holding it in place. There is one screw under screen, this screw can be removed by popping the plastic piece out of the screen right above it to gain access to the screw.
Electronics box cover removed. Remove 10 mm nut holding silver box
just to the right of the 214 relay to allow working room.
It is best to have two people to run the wire. Cut a coat hanger to be used as a fish. Ensure you remove the any sharp edges from the coat hanger to prevent damage to installed wiring. Remove the 10 mm nut holding the silver box to the right of the 214 relay seen in the picture above. Unbolt the support plate that has the stud on it for more working room, you'll need it.
Using a lubricant such as diluted dishwashing liquid or hand cleaner, lubricate the hanger. Insert the hanger into the location shown below in the back of the box. Be very careful and slide it along the installed wiring harness into the passenger compartment. This is where a second person is helpful. Make sure each person has a flashlight or drop light. The hanger will come out at the top of the relay panel. You'll have to peel the trim back to see it come through.
Insert the hanger through the wiring harness in the back of the box.
Hanger will come through at the top of the relay panel. You'll have to push the trim back to see it come through the installed wiring harness. Be extremely careful when pushing the hanger through.
Once it has been pulled through, attach the RJ-45 cable to it by securely taping it up. Lubricate the RJ-45 cable with hand cleaner or other type solution and have one person pull from the electronics box and the other should feed it from the passenger compartment. Pull it through to the electronics box. You will need no more than 12" of cable.
Attache the RJ-45 cable securely to the hanger and lubricate
before pulling through to the electronics box.
Pull the RJ-45 cable through into the electronics box
Connecting the RJ-45 Cable in the Electronics Box
Three wires will need to be cut in the electronics box and soldered to three conductors in the RJ-45 cable.
The three wires control:
- Ground connection to switch into tiptronic
- Ground connection to upshift while in tiptronic
- Ground connection to downshift while in tiptronic
These three wires are terminated in the electronics box at two 10 pin connectors, T10b (10-Pin Connector, yellow, connector station electronic box plenum chamber) and T10 (10-Pin Connector, blue, connector station electronic box plenum chamber).
If you look at the wiring diagram, the wires on T10b (yellow connector) position 6 is br/ro (brown/red) and position 7 is ge/bl (yellow/blue), and the other wire is located on T10 (blue connector) position 5 is ge/gn (yellow/green).
Pull the yellow and blue connectors. Find positions 6 and 7 on the yellow connector and make sure you have the correct wires above. You will notice that on the other side of the connector there is no terminal in these positions, the wires are terminated at this connector. Snip the wires close to the connector so you'll have the longest wire possible to work with.
Do the same thing for position 5 on the blue connector.
Disconnect the blue and yellow connectors and find the correct wires to cut.
EDITORS NOTE: I soldered the wires together, another alternative method is to crimp the wires together. However, if doing this, the proper crimper and lugs must be used. These wires are very small and require the correct size lugs and crimping tool for a reliable joint.
Once the wires are cut, reconnect the yellow and blue connectors. Strip the wires back in preparation for soldering them to the RJ-45 cable. Strip the RJ-45 cable back and strip three conductors. If you'd like to follow the wiring diagrams I did, strip the solid green, blue and orange wires of the RJ-45 cable.
Slide a piece of heat shrink tubing over one of the wires and connect the other wire to it. Solder the two wires together and heat shrink the tubing. Repeat for all three wires. Connect as follows:
- Yellow/Blue wire to Solid Green on RJ-45
- Brown/Black wire to Solid Blue on RJ-45
- Yellow/Green wire to Solid Orange on RJ-45
Three tip wires cut and ready to be soldered.
Three tip wires soldered and heat shrunk.
Once these wires are all soldered and the heat shrink tubing is shrunk, tape the wire up with electrical tape. Reconnect all the relay panels and put the silver box back in place. Tie wrap the RJ-45 cable in place. Do not place stress on the soldered connections, relieve the stress on these connections by tie wrapping around them.
Tip wires connected, taped and secured.
The work in the electronics box is now complete. Put the cover back on the box. Ensure the gasket on the cover is properly seated.
Wiring the New Shifter
Once I pulled the console and removed the old shifter, I discovered that the shifter assembly wire connector and wire colors are different on the 97 non tiptronic shifter and the 98 tiptronic shifter.
I decided to determine which wires are needed to connect the 97 electrical connector to the 98 tiptronic wires. These wires would be cut and the 97 electrical connector spliced in. The 3 new wires will be connected seperately to the RJ-45 cable.
If you are not comfortable with reading the Bently wiring diagrams and performing this to your car, STOP NOW! I found that the wiring diagrams and the actual shifters didn't match. After studying it for a while, I figured out what everything is and matched it up. The following table is what worked for me. I cannot guarantee that your used shifter will match the one that I did.
|Tiptronic Wire Connections for 1997 to 1998 Electrical Connectors|
|Wire Function||1998 Shifter Wires||1997 Wire Connector Wires|
|Shift Lock Solenoid||Black/Yellow||Gray|
|Shift Lock Solenoid||Red/Yellow||Green|
|Ground||Double Brown||Double Blue|
|Tip Selector Light||Double Grey/Green||Purple|
|Tip Shift||Yellow/Blue||Green (RJ-45 Cable)|
|Tip Engage||Brown/Black||Blue (RJ-45 Cable)|
|Tip Shift||Yellow/Green||Orange (RJ-45 Cable)|
Cut the electrical connector off the 1998 tiptronic shifter. Cut it as close to the electrical connector so the wires will be as long as possible. Pull the electrical tape off that wraps the wires. Verify that your shifter assembly has the same color wires as in the table above. If so, you can proceed, if not, you'll need to create a new table by tracing the wires.
Cut the electrical connector off the 1997 non tiptronic shifter, cut the wires as close as possible to the shifter to make the wires as long as possible.
Strip the wires and connect per the table above. Prior to connecting the wires, ensure the heat shrink tubing is on the wire. After connecting the wire, solder it and move the heat shrink tubing over it and shrink it in place. Perform the first 5 wires, leave the 3 tiptronic wires alone for right now. Tape up the wiring with electrical tape in a similiar fashion to the factory taping.
Reinstall the shifter to the car. Attach the shifter cable and shift lock cable. They shouldn't require any adjustment.
Mount the shifter back into the transmission tunnel. Be careful not to push the transmission cable gromet out of place! If so, you'll be sucking fumes after you shut down the car. Just make sure you look at where the cable passes through the transmission tunnel prior to installation. Make sure the gromet stays in place.
After the shifter is in place mechanically, you will need to make up the 3 tiptronic wires to the RJ-45 cable. If you use the wire configuration in the electronics box that was outlined above, connect the wires as in the table above. If you didn't use the same wiring method that I used in the electronics box instructions above, determine which wires need to be connected.
Now that the tiptronic shifter is installed and wired up, it's time to test it. Start the car, with your foot on the brake, shift into drive, ensure the shifter shifts and the dash lights are correct. Move the shifter into tiptronic and ensure the dash lights change to tiptronic mode. If so, your transmission appears to be working correctly! Run the shifter through all the standard gears. It won't shift out of first gear in tiptronic unless the car is moving.
The dash should shift to 54321 when the shifter is placed in tiptronic.
Reassembly the console assembly and take the car for a test drive!