C.1. Wiring the DFU’s
The first step in wiring the DFU’s is to install the ground wire. The DFU’s come from our factory
with a ground wire pre-installed on a tapped, un-anodized hole. This wire MUST be connected to
chassis/battery ground.
FAILURE TO DO SO MAY RESULT IN SEVERE ELECTRICAL SHOCK TO THE
USER!!
Electrical shock will occur if the DFU is not grounded, and someone touches it while touching
chassis ground (with the engine running). If desired, the ground wire may be relocated elsewhere on the
DFU chassis. However,
you will need to scrape off the anodization
from the chassis at the point of contact,
since the anodizing acts as an electrical insulator. Also, loose coil screws may cause an electrical shock as
well, since they must be grounded to the case at all times.
Always make sure that both the coil screws
and the ground wire are securely fastened.
After the DFU has been grounded, the rest of the wiring may begin. The DFU’s come shipped with
the appropriate connectors. Terminal D on all DFU’s should be connected to a
FUSED 12 VOLT SOURCE
that can pull
9 AMPS
of current. In the wiring harness, the outputs for Coils A, B, and C are routed in the
same shielded-cable housing. On an 8 cylinder, the outputs for DFU 2 (A2, B2) are routed in a separate
shielded-cable housing. These are all 9amp pull-to-ground outputs; that is, they create a ground path every
time a coil charges. When the coils fire, the outputs “float,” with no connection to ground or power. If the
wires need to be spliced or lengthened, 16awg wire should be used. See
Figure C.1. 1
for details on the
coil outputs in the wiring harness.
Figure C.1.1:
ECU Coil Output Wires (note: shield wire is connected inside the
TECgt
unit, not connected
at the coils).
WARNING:
The DFU chassis
MUST
be grounded. A ground wire must be connected to battery
negative, or to a good chassis ground.
FAILURE TO GROUND THE DFU’S MAY
RESULT IN SEVERE ELECTRICAL SHOCK!
Also, poorly grounded DFU’s may
result in poor engine performance, and can cause engine damage!! Use the drilled
and tapped hole next to the yellow connector for the ground wire. If desired, the
unit may instead be grounded at one of the four bolt holes. However,
you will
need to scrape off the anodizing under the bolt head
. The anodizing is an
electrical insulator, so unless it is scraped down to bare aluminum, it will not provide
a good connection to ground. If more than one DFU is used on a vehicle, each one
will require its own ground wire.
Additionally, make sure that the
coil screws
are fully tightened at all times!!
______________________________________________________________________________________
TECgt Manual Version 2.0
- Page 37 -
©2008 Electromotive, Inc.
