Haltech E8 - Manual (Page 15)

Haltech E11/E8 Instruction Manual
Power Relays
There are three relays used with the Haltech ECU, the main power relay, the ignition relay and the fuel
pump relay. These relays look almost identical, to determine which relay should go into which connector
the diagram on the side or top of the relay will need to be compared to the diagram in the Haltech wiring
diagram.
Figure 7 - Power Relay
These relays should be mounted on the firewall or an inner guard. Do not mount the relays such that they
could catch and collect splashed water. Residual water inside the relay housing will cause them to fail.
Mount them with the tab upwards as shown in the diagram.
Fuse Block Assembly
The fuse block assembly holds the fuses that protect the various components of the engine management
system.
The fuse block is supplied from the factory with fuses installed. The fuse ratings and connections are
shown in the wiring diagram at the end of the manual. The fuse ratings have been selected to protect the
Haltech ECU and the electrical systems that supply it. Fuse ratings should only be changed if the
expected normal load current exceeds the factory specification. Altering the fuse ratings could cause
severe damage to the system.
The fuse block should be positioned so that it can be accessed easily in case of fuse failure. Do not mount
the fuse block where it could be exposed to water. Mount the fuse block using the two screws holes in the
block ensuring that vibration will not cause the screws to vibrate loose.
Figure 8 - Fuse Block
Trigger Wiring (Crank and Cam Angle Sensors)
The most critical sensor on the engine is the engine speed sensor, without this sensor the ECU would not
know that the engine is moving and therefore it would never fire a spark nor inject any fuel.
The ECU gets information from the crankshaft and camshaft position sensors in the form of electrical
impulses over a period of time. When the ECU knows what pulses to expect it can compare this to what
pulses it receives and determine the engine speed and position at any point in time.
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