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MECHANICAL NEUTRAL SAFETY SWITCH CONSIDERATIONS:
Mechanical neutral safety switch configurations differ slightly in that they do not offer the same level of safety when installing a
remote start device. Often when the ignition switch is turned off while the gear selector is in any position other than park or neutral,
the mechanical function will not allow the key to be turned to the start position or be removed from the ignition cylinder. This
configuration prevents mechanical operation while the vehicle is in gear but offers no consideration for electrical operation.
Because of this potential problem, this installation requires the additional connection of a safety wire from the remote start device to
the vehicle Park/Neutral ECM Input or the vehicle key in sensor. This connection will prevent remote start operation if the key is left
in the ignition switch regardless of the gear selector position.
PARK / NEUTRAL ECM INPUT:
The Park / Neutral ECM input is the preferred method of installation. This not only maintains the integrity of the factory circuit, it is also
the easiest to install, providing the vehicle you are working on has this ECM input.
The installation required for this application (shown below), indicates the slight reconfiguration of the control switch wiring and the
addition of a 4000 series diode. Shown is a typical GM Park/Neutral ECM input circuit. To connect the Audiovox remote start unit to
the GM Park / Neutral ECM input:
1. Locate the Orange / Black reference wire in the "C2" connector found at the ECM in GM B Body vehicles or, locate the equivalent
reference wire in the vehicle you are installing the Audiovox Remote Start Unit in.
2. Connect the Cathode, (Striped) end, of a 4000 series diode to this reference wire.
3. Connect the Anode, (Non Striped) end, of the diode to one side of the Remote Start enable switch.
4. Connect the other side of the enable switch to the Black/White enable input wire of the Remote Start unit.
The reference diagram below shows a typical GM B Body ECM reference wire and how it is to be connected to the Remote Start Unit.
KEY IN SENSOR CIRCUITS:
If the vehicle you are working on does not have or you cannot locate the ECM reference wire, there are two alternatives
available. Although not preferred, the vehicle Key In Sensor may be reconfigured to allow a margin of safety and will
prevent the vehicle with a Mechanical Neutral Start Switch from starting in gear.
AUDIOVOX ADVISES THAT YOU MAINTAIN THE FACTORY CIRCUIT WHENEVER POSSIBLE. The following two
circuits may be used only if the above circuit is not available.
NOTE:
When completing an installation using either of the following key in sensor circuits, if the operator inserts the
ignition key while the vehicle is running under the control of the Remote Start, the vehicle will shut down. This
must be explained to the operator as it is in contrast to the normal operation of a vehicle utilizing an electrical
neutral start switch and is inconsistent with the operator's manual.
Additional information concerning Key In Sensor methods 1 & 2 are listed below and should be reviewed before
considering either alternative.
Method 1 will allow the safety required for the remote start unit and prevent the vehicle from starting while in any gear
other than Park or Neutral while the key is in the ignition cylinder. However, if the key is left in the ignition switch and
the door is left opened, the added relay will be energized causing a 150mA drain on the battery.
Method 2 will allow the safety required for the remote start unit and prevent the vehicle from starting while in any gear
other than Park or Neutral while the key is in the ignition cylinder. However, the original factory key in chime module will
not alert the owner that the key has been left in the ignition switch. In addition, this may also effect other warning tones
such as the light on reminder.
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