Haltech IG5 - Manual (Page 38)

34
back and check all the angles again. If you have guessed the trigger angle, try and calculate it
properly. Remember that the angle is in crankshaft degrees, not distributor degrees. Also
make sure the correct trigger edge is selected (rising or falling).
If the angle is a little out alter the angle in the Trigger Degrees field. If the correct timing
lies outside the 60° to 100° range permitted in this field, mechanical changes will have to be
made to the trigger set-up. If timing reference is taken from a distributor, then you may be
able to rotate it while using the timing light until the engine is at 10° BTDC. Be wary about
adjusting the base timing in this manner by any more than a few degrees as it can upset the
rotor phasing. For details on rotor phasing, see Appendix D.
When the base timing is verified as correct with the timing check “on” the engine may be
started. You must now ensure that the timing does not move as the engine speed changes.
Give the engine a few quick revs while using the timing light to check that the ignition timing
stays at 10° BTDC. If the base timing is locked at 10° BTDC and does not change with
engine speed then you are ready to load an Ignition Timing Map and turn off the Timing
Check Flag.
If the ignition does change with engine speed then see the Troubleshooting procedure in
Appendix A
5.4 Loading an Ignition Library Map
The IG5 has an effective and time saving method of programming the ignition curve using
Library Maps. Each ignition timing Map in the library is slightly different. By becoming
familiar with the library you should be able to select an ignition timing Map that will suit your
engine. Each ignition timing Map in the library is accessed by a different name. The name
reflects the characteristics of the Map. Names can be up to eight alphabetic or numeric
characters in length. The ignition timing library Maps use these eight characters as shown,
where the first character is always a number.
•
The first two characters in the ignition timing Map name specify the ignition timing to
be used at idle. The example Map name shown has 15 degrees of advance at idle.