Fueltec FT 500 - Black wire - batterys negative; Black;White wire - power ground

28
Black wire
This wire is responsible for signal ground to the ECU so, it must be connected
terminal, with no seams. Under no hypothesis, this wire can be connected to the vehicle chassis or split with the ECU
black/white wire (power ground). This will cause electromagnetic interference and other problems hard to diagnose and
solve.
switches, car alarms or others. To turn a FuelTech ECU off, the red wire should be switched on and off.
 Negative for sensors (TPS, air temp., pressure, rpm, distributor, etc.): It is vital to use sensors ground straight to
Connecting them to chassis may cause electromagnetic interference, wrong
readings or even damage to the sensors.
 Attach the negative wires to the battery terminal use ring terminals and avoid soldering them. A well crimped
terminal has better resistance than a soldered one. Besides that, solder makes the joint stiffer, and less resistant
to vibration, typically found in automotive applications.
 Use a crimping tool and insulate the wire with insulating tape or heat shrink tubing.
 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
point. 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
the shield is connected an 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.
NOTE: it is very important to check the shield that connects the engine block to the chassis and to the battery. If this
shield 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, ther
 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 .