FT500 SFI / FT500LITE SFI
29
Electrical installation
•
If there’s a need to solder the wire to the terminal, check it`s
resistance after the solder, it should be lower than 0.2 Ohms.
Obs.:
If corrosion is found (green/White powder) on the battery
terminals, clean it with a wire brush and baking soda or contact cleaner
spray. Double check the terminal holder and replace it if necessary.
Check resistance after the cleaning, it should be lower than 0.2 Ohms.
Black/White wire – power ground
These are the ECU power ground wires. They must be connected to
the engine block or head in a place with a good electrical contact.
The same shield that goes from the chassis to the battery’s negative
terminal is a good contact point.
Under no circumstance this wire
can be connected straight to the battery’s negative terminal
or in
the same point that the ECU black wire. This will cause electromagnetic
interference and other problems hard to diagnose and to solve.
The three power grounds (24 and 16-way connectors) must have
permanent contact with the engine block/head, never being connected
to switches, car alarms or others. To turn a FuelTech ECU off, the red
wire should be switched on and off.
Power ground to ignition modules (SparkPRO, etc.), Peak and Hold
drivers, relays and other accessories, must be connected to the same
point, at the engine block/head.
A good test to check if the power grounds are with good connection
is, using a tester, to measure the resistance between the battery’s
negative terminal and the chassis ground. Connect the red probe on
the chassis point that the shield is connected and the black probe
on the battery’s negative. With the tester on the 200ohms range, the
resistance measured must be below 0.2 Ohms.
Remember to touch both probes to check its resistance. This reading
must be subtracted from the first reading to found the correct value.
OBS:
it is very important to check the shield that connects the engine
block to the chassis and to the battery. If this Pshield is defective,
replace them by a new one, as it may cause serious damage to the
ECU and its sensors. For this reason, we recommend to use two of
these shields.
Main switch installation (optional) – important tips
Main switches have been used for a long time in competition vehicles
for safety purposes in case of an accident. Just like any other electric
accessory, there’s a correct way to install it:
The main switch cannot be connected to ground or power
ground, under no circumstance!!
This is the most common error by
installers and, usually costs hours of work to fix all the problems that
it cause. All of this without counting the huge possibility of damaging
all the electronic accessories on the vehicle.
The main switch must
ALWAYS control the battery’s positive (12V)
.
1
2
3
6
FT black/white wire must be
connected to engine head
5
4
1 - Shield connecting battery negative to chassis and engine;
2 - FT black wire Battery negative;
3 - Positive wire to alternator;
4 - Main switch;
5 - Ignition Switch;
6 - Switched 12V;
