Starter security replay question, not click/click/start
 

Hi guys,

Another starter/security relay related question, but this isn't the typical click/click/start issue. I added the pettit style starter relayed to my car in the past to fix the click/click/start issue. This is a new issue.

My battery was dying and I tried to start the car a couple times causing the relay to click on and off at a very high rate and I think I might have damaged something. Quite often now when I go the start the car there's no click at all and the starter doesn't turn. The odd thing is I can hear the security relay randomly clicking on and off while the key is in the acc on ignition setting. If I catch it at the right point between clicks and try to start the car it'll start fine.

So basically whatever causes the relay to trigger is sending a very inconsistent signal. I replaced the security relay thinking that I had gone bad, but the new one does the same thing which is what leads be to believe it's something further up the circuit. I pulled out the security relay and added the jumper wire and it starts fine every time. So seems like a possible long term solution but my OCD side wants to get to the true root cause. Any thoughts? My car has an aftermarket alarm installed. The installer left an insane mess of wiring so I'm wonder if something has gone bad there, possibly a splice has gone bad....? I'm not really sure how the aftermarket alarm taps into the stock alarm wiring tbh.

Most likely something with CPU #2 (the black box) as that has all the security system stuff in it. I doubt an input to it would cause it to flicker that relay, that sounds like a bad connection/solder joint kind of thing.

Dale

^Replacing the CPU#2 with a new one solved my intermittent gremlins related to starting. Definitely a bit pricey vs. a simple jumper wire. But it was well worth the peace of mind for me. If on a budget, jumping the relay is the easy choice.

FD01-67-560B Control Module (CPU#2) can be had at Tasca parts for approx. $250. You can also check with Ray Crowe for availability through Mazda.

I thought that would be more pricey new! May have to get one, mine has always been flaky :).

Dale

Hmm interesting. Thanks for the input. Any idea if there's a capacitor or something like that that tends to go bad in there? That was common on NSXs. Early ones had caps in the hvac controls that would leak after a while. I replaced all the caps and everything worked fine again. Wonder if the same can be done with this cpu #2 module.

There's a primary circuit board within the CPU#2 module that you can access after prying the back cover off. On that board is where you likely have a diode component or similar leaking/corroding/misbehaving. For me, it was just easier to replace the module with a new one, and be done with it. But there are other forum members who have had success refurbishing various components on that board I believe. (Or maybe I'm thinking about the ABS module that has similar components that go bad, and then cause the blinking code errors on the dashboard. Unfortunately, that module is no longer available brand new.)

Maybe your problem is with the clutch starter switch. I have removed both the clutch switch and alarm starter relay and this has solved all the start problems with my 92 FD.