The M36T2 immobiliser is a two circuit Thatcham approved immobiliser, it is manufactured with very high quality components to a very high standard & as such this is one of the most reliable immobilisers manufactured today, many of these systems are still working perfectly on vehicles which are well over 15 years age.

 

The problem, relay 1 (circuit 1) of the immobiliser can handle a maximum of 10 Amps, relay 2 (circuit 2) can handle 25 Amps. Here's the rub, TVR have wired these circuits the wrong way around, the TVR fuel pump circuit goes through the higher rated relay 2, while relay 1 (rated 10A) has to handle the starter circuit. All being well there are no problems even though the two relays are wired the wrong way around, as testified in that they've been functioning perfectly for 10 years or more. Problems arise when the starter solenoid begins to wear, in so doing it demands more & more power to function, when the current flow to the starter gets to the 10 Amp limit of relay(1) problems start, this gets exasperated when the engine is hot which in turn makes the solenoid hot which in turn requires even more power, I understand this is known as the hot start problem, this demand for power will eventually burn out the smaller relay. Adding an extra 'hot start' relay to this circuit is not a premanent fix, this circuit will just demand more power which could eventually burn out the ignition switch or associated wiring to eventually the failure of the starter itself. Before this happens we recomend to have the solenoid/starter inspected & have it repaired or replaced if found faulty.