95 Camry ignition cutoff circuit?

Question

I have a dealer installed LoJack alarm. I have figured out from poking around with it that the car has an ignition cutoff circuit that makers of alarm systems use. Can somebody tell me how that works?

I'm having electrical problems involving the LoJack and corroded wires. After the car sits all night, it won't start on the first try in the morning. I have to turn off the radio and the heater and try again. Usually it starts right up at that point.

The LoJack stores new settings in itself when the ignition is turned off. And after X minutes, it automatically enables the alarm system, but I keep it in "Valet Mode" and it shouldn't do that. BUT a year ago, the Valet Mode switch had a broken wire and it behaved strangely then.

TIA.

Wolfgang · Accepted Answer

LO-Jack is a hidden radio transmitter that is activated when you report your car stolen -- Police with aid of the LO-Jack company can then track location of your vehicle and recover it -- all guaranteed with 24 hours of being reported.  Was your install a customized one that also includes an immobilizer alarm that's probably tigger off a current draw?  When did you have it installed --- thought they came with a 5 year warranty?

Stubby · Answer

The LoJack was installed at the car dealer by a LoJack guy. It was a very clean car with only 20K miles. But it lacked the remote door unlock feature so they sold me a Lojack. That was fine for awhile.

Then there were many problems with the locks and with starting the car. The dealer sold me a new alternator and several $150 service jobs, none of which fixed the real problems.

So I decided to figure out what was wrong and pulled of the kick panel by the driver's door. Lojack connects to three car wires near the connector block one the door that is used for locks and windows. Several of those connector terminals were severely corroded and crumbled as I examined them. [I suspect the dealer used battery acid to guarantee some future repair work!] I soldered in jumpers around the connector for 4 signals. It has worked normally for several years, but maybe another pin has corroded away.

In the whole process, I removed the LoJack box and wrote down the signals and wire color codes used. I noted one was the "ignition lock out" signal. I want to know how that works. I suspect it is a wire that you (or a LoJack box) can ground that operates a relay that opens the ignition key switch circuit. But that's only a guess. Can somebody tell me?

Wolfgang wrote:

95 Camry ignition cutoff circuit?

Join the Discussion

Didn't find your answer?