Intermittent immobilisation. Random crank but no start, with immobiliser light flashing on the dash. Vehicle may start normally once or twice, then immobiliser lamp flashes and it will not start. Vehicle has an aftermarket key, with a genuine key on order.

Vehicle presented with an intermittent crank no start that appeared immobiliser related. Scan revealed an immobiliser communication fault between the immobiliser control module (key reader/ICM) and the ECM, plus an ECM control module performance code. After inspection of fuses, connectors and key transponder related components, the root cause was found to be a poor engine earth connection creating unstable module power and communication integrity.