Hello, I have a 1990 Nissan 300ZX with Viper 700ESP alarm and 515 siren. It was already installed in the car when I bought it, and the only problem I've had is that the siren stopped chirping about a year ago. The alarm continued to arm and disarm using the transmitters, until yesterday, when neither transmitter would disarm, nor open the doors. I opened the passenger door with the key, but when I tried to start the engine, it was immobilised, but all accessories worked. I have tried turning the siren switch to OFF, and disconnected the cars 12v battery, but on reconnection alarm is still armed.
Hazard lights flash when I try to start the engine, and the LED flashes 5 times (=ignition trigger). When I turn off the ignition, LED continues to flash 5 times, until I lock the car doors when LED flashes 3 times (= door trigger).
I don't know where the valet switch has been installed, and not sure where control unit is (behind dash, above pedals?) I have found a long triple conductor cable disconnected at one end. Is this the programming cable, so other end will be connected to control unit?
I cannot disarm using the transmitters, nor by switching to OFF on the siren box. Would turning off the siren, then disconnecting cars battery, together make it forget it is armed?
Near the ignition switch, there is a bit of "homemade" harness wrapped with insulation tape, and this harness has a 15amp fuse on it. But it doesn't look simple to find which wires to cut, and which to rejoin to disconnect the control unit, and renable starter. If I take the fuse out, hazards stop flashing, but starting still immobilised. My car has aftermarket Turbo Timer and APEXI turbo controller installed also. We have had very heavy rain recently, and my car sits out. The car worked normally the first day after, but second day no response to transmitters, and I am unable to disarm. I know corrosion can "grow" in connectors after rain, but most components being so well hidden, I don't think they'd get wet, only the siren might get wet from a hood scoop hole, and it hasn't had a rubber cap over the switch.
Update: I can now start the car by cycling the Siren key OFF then ON, but I still can't arm or disarm using the transmitters. So I have to go under the bonnet (hood) every time I want to start the engine. So the immobiliser logic seems to be working, but no remote control!