10/17/2019
Tom's Garage of Clarksburg, NJ is excited to announce we are now offering automatic transmission controller (governor) repair/rebuild services for the Renault AT 4141 gearbox to the general public. This controller was used in DeLorean, Alpine, Zimmer, and Renault. While most (possibly all) other vendors are now offering a complete board replacement with a PIC micro controller marketed as an "upgrade", we believe the the long term impact of the new design is still unknown and has the potential to be bad. Bench testing the new design compared to the old one does demonstrate some obvious behavior differences that may cause unintended consequences. Our preference is to stick with the design as originally intended by the group of designers, engineers, and quality assurance professionals who had much higher performance and reliability standards to meet than the designer of the current replacement. In addition, the process to replace the boards requires drilling out the original epoxy that holds the wire in to the housing, increasing the risk of environmental damage from water, salt, and other contaminants getting in, as well as damage from strain on the wire.
There are two manufacturing versions of the original design, and each tend to have different problems. The earlier boards most likely fail because the two electrolytic capacitors literally blow up. It may be from age, heat, voltage spike, or a manufacturing defect of the component. The later boards are more likely to have manufacturing quality issues, typically poor solder joints. In some rare cases, the power transistors may also be damaged.
For many years, the repair process has been public knowledge, and some owners have done it on their own. There is no "secret" to this repair, but it is time consuming to do it properly. At Tom's Garage, once we receive your complete assembly, we will clean it externally in our environmentally friendly parts washer. Then the unit will be opened, and inspected. The original conformal coating is then stripped from the board. New "solid" style Tantalum capacitors rated at 50V (over-rated for reliability) will replace the original aluminum ones, then each solder joint will be re-flowed and repaired. The unit will be tested to make sure it is working properly, then new conformal coating will be applied. Finally, all of the old silicone will be removed, and the unit will be resealed with fresh RTV. Once assembly is complete, it will be tested again before it is shipped back to you.
Do you have a "bad core"? If your wires are burnt, we may be able to repair that too. The repair will be apparent visually, but the unit will function properly.
Because we are rebuilding your part, and not swapping it, please allow for extra time to do the work.
Please contact us by email, phone, or FaceBook to arrange for your repair.
[email protected]
https://www.facebook.com/Tom.Garage/
(732) 835-6610
