Haltech F9A - Manual (Page 97)

96
5.10 Turbo Timer (TT)
When an engine is switched off, oil is no longer being pumped to the turbocharger. This is
common cause of turbo wear if the turbocharger is no allowed to slow down before an engine
is switched off, cause it to spin for an extended time unlubricated. This function controls the
ignition power via relays to keep the engine running for a period of time after the ignition
switch has been turned off.
Care should be taken to make sure the relays are wired correctly, and that an over-ride switch
has been fitted to allow the engine to be switched off manually while the turbo timer is active.
See figure 5.7 for the correct way to wire this output. The ECU detects if the ignition switch
has been turned off via the Auxiliary Input/Output. Therefore, the Auxiliary Input/Output
Function must be selected as Turbo Timer in the Identification.
There are three programmable parameters. The first two are the minimum Air Temp. and the
minimum Coolant Temp. If the inlet air and the coolant temperatures drop below their
respective values, the output will switch off. The last parameter is the Run Time. This is the
maximum time the ECU will allow the engine to continue to run after the ignition switch has
been turned off. If either of the temperature conditions are meet before this time, the output
(and therefore, the engine) will switch off. The Run Time is set to the nearest half minute.
Figure 5.7
NB: When using the Turbo Timer function, the Aux. In/Out Function in the Identification
must be set for Turbo Timer. When using TT, other functions that use the Aux. Input/Output
line can not be used.