Suppose your 993 remote keyless entry fob works only from very close to the car, even after replacing the fob battery. In that case, the range can be dramatically improved by replacing some inexpensive failed capacitors. The capacitors are in the immobilizer controller under the driver's seat on US-delivered cars.
This is simply the result of two capacitors drying out with age, which affects the radio receiver range in the controller under the driver's seat. If one is handy with electronics, replacing the two capacitors is not too difficult. In fact, the hardest part of the job is removing the seat and the shroud covering the controller beneath it.
Here are the steps to gain access to the Immobilizer/Fob receiver and the DME controller:
- Disconnect the car's battery before starting the procedure.
- Remove the driver's seat on left-hand drive cars. Here is how to do it with a minimum of drama.
- Drill out the security rivets on the cover over the controllers under the driver's seat.
- Use a shop vacuum to clean out the metal shards left from drilling before unplugging the controller to avoid contaminating the electrical connections.
- Replace the cover when finished with self-tapping machine screws, as the cover may provide the required electrical shielding.
- Detach, unplug, and remove the black plastic controller box next to the larger metal Bosch DME ignition controller.
- Open the controller's housing and locate the two electrolytic capacitors, which look like small metal cans wrapped in plastic shrink wrap on the circuit board.
They are labled as follwed:
- 330uF/10V, In plain English, 330 Microfarad, 10 Volt electrolytic capacitor
and a
- 0.47uF/50V capacitor
Replacement capacitors can be purchased on eBay or at any electronics supply house, for example:
Be sure to pick ones with similar housings to the originals ones to facilitate the reinstallation.
- Note the polarity of the old capacitors by the markings on their cases when removing them (see below), and install the new ones, placing the wires marked (+) and/or (-) in the same mounting holes as the original ones. Usually, only one wire lead is polarity marked on the side of the capacitor body.
Removing and replacing the capacitors is relatively easy if you are handy with a soldering iron; however, the circuit board is a two-layer board with wire traces on both sides, so...
- Be sure to unsolder the capacitor leads to both the front and back of the board as needed.
- Be sure to use lead-based rosin core solder, NOT the newer lead-free alloys that require heating to higher temperatures and
- Use a low-wattage pencil-style soldering iron, max 35 watts.
- Use care not to overheat the board and solder the replacement capacitors to both the front and the back sides of the circuit board's mounting holes.
- The wire traces are very close together, so use a magnifier to check that the solder joints are good and that you didn't inadvertently jump and join an adjacent wire trace.
- Once the new capacitors are installed, button things back up, reattach the battery, and you are done!
Updating the capacitors has resulted in my fob working from as far away as I can get from the car in my drive, where previously, on a good day, it would only work from five or six feet.
Addressing odd turn signal behavior:
- The exterior right or left-hand signal lights (front and back) stay on, not blinking, regardless of the ignition or turn signal position, and
- The dashboard turn signal indicator also stays on, not flashing, and
- When the emergency flashers are activated, no blinking may occur
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#Alarm #fob #door lock #immoblizer #ignition kill #led flashing, #remot #entry #lighting
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