The Module is OK. Your Voltage is too low.
The ignition needs 2S LiPo
If you use nicad cells, be sure to have 6 cells.
BTW, there should be an orange label on the HT lead that states the required voltage. The ICU-L ignition starts to act up below 6.4 Volts. I believe the newer versions can operate down to 6.0 Volts though.