J&S Electronics
13925 Parkway Dr. Garden Grove, CA 92843
(714) 534-6975 www.jandssafeguard.com
1) The SafeGuard control unit must be mounted inside the passenger compartment. We recommend hiding it under the
carpet on the passenger side.
2) The supplied harness is ten feet in length. This allows you to connect either in the engine compartment or directly to
the ECU. If you choose to install in the engine bay, feed all the wires through the firewall. Make sure you leave enough
wire inside the car so you can adjust the unit on your test drive.
3) In general, the unit installs between the factory ignition module and the coil negative, but the unit has been designed
to accomodate many other triggering modes.
4) The J&S Green wire will connect to the “points” or distributor end of the cut ignition wire and the J&S White wire will
connect to the coil side of the cut wire. Dress the J&S wires, cut them to proper length, and crimp on the matching
connectors.
5) Ground the J&S Black wire.
6) Using the wire splice provided, connect the J&S Red wire to the coil positive wire.
7) The mounting hole in the Bosch sensor is 8mm or 5/16”. Locate a bolt in the block with an 8mm or 5/16” bolt to mount
thesensor, and torque to about 15ft. lbs. Route the gray knock sensor cable, and connect to the sensor.
8) The unit requires a source of manifold vacuum. With switch 8 up, the unit is not armed to detect knock until the
vacuum is less than five inches. Switch 8 down, the unit is not armed to detect knock until the vacuum goes below 15 in.
The brass tee fittings included in the kit let you tap in to the 1/8” teflon tubing used on most boost gauges.
9)
Switch Settings
Set the Mode Select switches at the front of the unit as follows:
Switch 1 is the 10°/20° range switch. Down
is 10° max retard, up
is 20° max retard. For now, leave it
up.
Switch 2 is the retard all/retard separate switch. Up is retard all. Temporarily set switch 2 up.
Switches 3 and 4 select the number of cylinders. Use the following table:
S3
S4
1
1 8 cyl
0
1 6 cyl
NOTE: 0 = down
1
0 5 cyl
0
0 4 cyl
If RX7 version, set S3 and S4 both down.
Switch 5
configures a pullup or pulldown resistor on the digital input pin.
In general, leave up (pullup).
If installing between ECU and MR2 or RX7 igniter, set to down.
Switch 6
configures the unit to trigger on rising edge if up, or falling edge if down.
In general, leave up,
unless
installing between ECU and factory ignition module. Note that Honda ignition module is reversed.
Switch 7
configures the polarity of the output pulse on both the “Aux” pin and the “Mag Out” pin. Spark on rising
edge if up, falling edge if down. In general, leave up, unless installing between ECU and stock ignition module. Note
that Honda ignition module is reversed.
Switch 8
is the FI/NA mode switch. Up is forced induction, down is naturally aspirated. With switch 8 up, the unit is not
armed to detect knock until the vacuum is less than five inches. Switch 8 down, the unit is not armed to detect knock
until the vacuum goes below 15 in.
SafeGuard Installation
