Haltech IG5 - Manual (Page 56)

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13.4 Torque Converter Lockup (TCC)
This function controls the clutch lockup solenoid on automatic transmissions. Locking the
torque converter reduces the amount of energy lost through the transmission, providing better
fuel economy.
The solenoid activates whenever the road speed is greater than a programd value for a given
throttle position. The solenoid will only activate if the engine temperature is higher than 46°C
(118°F), and will be disengaged if the throttle position exceeds 70% or road speed falls below
64kph. The TCC function also provides for a 4th gear/transmission over-temperature switch
input. This signal indicates that the transmission is hot, and engaged in top gear. When this is
the case, the lockup solenoid is activated regardless of road speed whenever the throttle is
more than 4% opened.
To use the TCC function, you must have the following:
- a square wave signal road speed indicator whose frequency is proportional to road
speed; (this may require a unit for signal conditioning, such as the Haltech
TM Reluctor
Adapter)
- access to the wiring of the torque converter lockup solenoid and 4th gear/over temp
switch;
- IG5 programming software and cable.
Wire the TCC solenoid to the appropriate output line on the Auxiliary I/O connector, and, if it
is available, the 4th gear/over temp signal to the Aux. In line (the blue flywire on the IG5
main harness.) The 4th gear/over temp signal must be a pull-to-ground style signal. If you are
not using this feature, leave the blue flywire disconnected, but insulate the end to ensure that it
will not short to the bodywork.
To determine vehicle speed, a square wave signal must be applied to the road speed input
connector. This connector possesses ground and 12 volt signals for powering a Hall effect or
optical sensor. A magnetic or reluctor type signal is incompatible, and you will need to
convert the output from this style of pick up to a square wave. The Haltech
TM Reluctor
Adaptor would perform satisfactory conditioning.
Once the wiring is complete, run the IG5 software in Online mode and go to the Identification
page. The parameter Road Speed Value must be set with the number of pulses expected per
kilo-meter. If you are unsure of the exact value for this parameter, enter an approximate
number and check against the vehicle's speedometer. Adjust the Road Speed Value until the
road speed displayed on the Engine Data Page and the actual vehicle speed agree.
Go to the Options page in the software, and select the Torque Converter Lockup function on
the appropriate output. The map for the TCC function indexes the vehicle road speed against
the throttle position. When, for any given throttle position, the road speed is greater than that
displayed in the map, the solenoid will be energised. The road speed must then fall 8 kph
(5mph) for the clutch to be disengaged. This 8 kph hysteresis should prevent solenoid
oscillation during cruising near the cut-off point. The default map activates the solenoid at 70
kph at smallest throttle opening, and increases the activation threshold to 160kph at 70%
throttle. Although this map may be customised as required, it is advisable to never engage the
lockup below 60 kph (40 mph).