10
11
NEXUS R3 CONNECTIONS
Main Power and Ground
The NEXUS R3 must be connected to battery
positive and battery negative at all times for
correct operation.
Connect the NEXUS R3 to the positive battery
terminal via the supplied RED SurLok connector
using a 4AWG cable and to the negative battery
terminal via the black SurLok connector using a
4AWG cable.
+
-
Battery Ground Output
The battery ground output pins (A10, A11) are
capable of 3A per pin and are directly linked to the
battery negative stud internal to the NEXUS R3.
These pins can be used for cable shielding
connections or to ground low current CAN devices,
digital sensors, or switch grounds.
These battery ground output pins are NOT meant
to ground the VCU and should not be connected to
battery negative or the chassis.
CHASSIS /
ENGINE /
BATTERY
GROUND
PIN A10 / A11
Ignition Switch
The ignition switch input pin (A13) must be
connected to a sw12V source to turn the
NEXUS R3 on.
Method 1:
If wiring to an existing ignition key
switch in the vehicle, it is important to make
sure to wire A13 to the main ignition wire (i.e.
not accessory) so it doesn’t loose power while
the engine is cranking causing the VCU to
momentarily turn off.
Method 2:
Alternatively, the ignition switch input
(A13) and the low c12V power source
(A26) can be switched together to turn the VCU
On or Off.
NOTE: Pin A26 is a low c12V source and
must not be used to power any other device in the
vehicle. Insulate and isolate if not used.
BATTERY
ACCESSORY
IGNITION
START
IGN SW INPUT
IGN SW INPUT
(LOW CURRENT)
SWITCHING THE VCU ON (METHOD 1)
SWITCHING THE VCU ON (METHOD 2)
+12V
MOUNTING TEMPLATE
50mm
21mm
(Subject to tolerances)
SurLok terminals installed
