1995 3000GT VR-4: Making OEM Keyless Entry Work With a Turbo Timer

• Why Do I Want To Do This?

  • If you do not have an aftermarket alarm and use the OEM keyless entry feature, you may find that your OEM keyless entry does not work when the Turbo Timer is actively running the engine (key is not in the ignition).
  • Based on experience with my car and descriptions of others' cars, the lack of keyless entry functionality seems to be directly related to the Turbo Timer's providing power to the car's accessory (ACC) circuit. In other words, if the accessory circuit is powered, keyless entry is disabled; and if the accessory circuit is not powered, keyless entry works normally. You can test to see if your Turbo Timer powers the ACC circuit by trying to turn on your radio while the Turbo Timer is running the car. No radio = no power to the ACC circuit. If you do not have a radio, the cigarette lighter and the windshield wipers are other things powered by that circuit.
  • So far, I've verified that with an HKS harness, the Blitz DTT-X Turbo Timer and the Defi Turbo Timer both power the ACC circuit. Michail Wilson reports that the new Blitz DCC Turbo Timer installed with the Blitz Harness does not power the ACC circuit. If you have more data to report to this effect, please e-mail me.
  • In summary, if you find that your Turbo Timer powers your ACC circuit and you want use of your keyless entry, you'll need to follow the instructions below to disable that feature of the Turbo Timer.




• How Long Will It Take Me To Do This?

  • If you're in the process of installing your Turbo Timer, this will take you all of 10 seconds.
  • If you've already installed your Turbo Timer and want to do this modification, it'll take you however long it takes to access the wiring for your turbo timer plus 10 seconds.




• Anything I Should Do Prior To Attempting This Procedure?

  • Access your turbo timer's wiring through whatever method is most convenient for you.




• What Mitsubishi Parts Will I Need?

  • None.




• What Other Parts Will I Need?

  • Electrical Tape or Wire Caps




• What Tools May/Will I Need?

  • Wire Cutters

The Procedure

	Examine Turbo Timer Harness
	Shown is the HKS MT-1 Turbo Timer Harness. It has 3 connectors on it: one male/female pair of connectors for the OEM ignition switch harness and one 3-pin connector for the Turbo Timer. The harness is essentially a pass-through connector for the ignition switch wiring, with taps (tees) into the battery(B+), ignition (IG1) and accessory (ACC) circuit wires. Your wiring harness may have different colors than mine, but on my harness, the ACC wire was the blue one. See below for schematics and an explanation of how this modification works.
	Schematic of the Stock Ignition Switch Circuit
	Here you can see how the stock circuit works. The blue box represents the ignition switch in your steering column - that's the thing you stick your key in to start the car. It has 4 positions: Off, Acc, On, and Start. Each of these positions causes a different set of the 6 wires in the harness to be connected. The black dots indicate a connection when the switch is in that position, and the intersections without the black dots indicate that there is no connection.
	Schematic of the Ignition Switch Circuit With Turbo Timer Added
	Here you can see how the circuit works once the Turbo Timer harness has been installed. Note that the shaded region represents the non-OEM parts added to the car. As indicated, you need to cut the blue wire to disable the accessory circuit while the Turbo Timer is running the car. I have seen no negative effects of this modification in my car, and my keyless entry works perfectly.