Full Disclosure...

The car was operating almost perfectly as far back as 7 months ago when I wrote this post...

https://www.rx7club.com/interior-ext...noise-1092190/
Synopsis... The radio started making crackling noises. The problem went away and I had not heard it again until two days ago.

I had only three problems that I knew of:

1. The ABS would cut out and the warning light come on sporadically - but usually after a mile of travel.
2. The CEL would come on for the EGR error I have had sporadically since buying the car 17 years ago.
3. As of about 4 months ago the right window stopped raising. I was planning to tackle this on this week.
4. Other than the above, the car had been great. About two months ago, the Tachometer, Speedometer, Odometer, Cruise Control, and Cigarette Lighter all stopped working. It all came back one day later, then two days later they all failed for good.
5. Because I was coming up on a deadline for a non-car project. I decided to leave the car be until I finished the other project.
6. Two weeks ago, I ordered a solder rework kit to see if I could get the gauges working again. When the kit arrived, put a charger on the battery so I could start it and drove the car a few times.
7. Yesterday, the starter would not spin. I popped the clutch to get the car back home.
8. 1 new battery, and 1 rebuilt starter later, I still get no start.

When I turn the key to the on position (not start), there is a click-clack noise from the dash? Foot-well? Then when I turn the key to start, there is nothing - no sound - the lights dim a bit and that is all.

I checked all the fuses - engine bay and interior and they all "look" ok. Tonight I will try to dig up the procedure for bypassing the clutch interlock and see if that is the problem.

 

Have you checked your security relay?

 

Thanks,

Electrical is a mystery to me... I have read several posts about this but not sure I understand it...

• What I understand is that there is a voltage drop in the starter system wiring...
• This drop prevents enough voltage from getting to the security relay...
• My normal desire is to replace things that are broken and not bypass them...
• But in this case, if I were to just replace the security relay, it will not fix the problem because the replacement relay may work "better" but still will not get enough voltage to start the car. This is why jumpering works?

If this ^ is correct, then I will go ahead and try to jump the relay (is 10 ga sufficient?) and see what happens.

If this does or doesn't work, is the true fix to replace the battery harness with a new (fresh) unit? I know this is a expensive fix... How hard is it to make a new battery harness? And more importantly, how hard would it be to get the old one out and a new one in?

 

Yes that is correct ^. What I did was de-pin the wires from the connector & added a male/female on each wire end to join them, this still lets your security alarm function. If you would like pics let me know and good luck.

Before replacing the harness I would test for voltage drop at the starter, test your 12v cable coming from your battery to starter motor & also test your 12v switch wire (black/red) the smaller wire that's connected on the other side of stater motor.

 

Check that the rubber stop on the clutch pedal has not broken out, it's purpose is to depress the clutch switch. When it falls out, it allows the plunger on the switch to pop through the hole, preventing the starter from working. This is a very common problem, that is remedied with a short bolt and nut.

 

A non start issue can be caused by a dirty clutch switch (the one next to the fuse box). Taking the switch apart, and cleaning it may fix your problem. Its not difficult to do this.

 

Bringing this back from the dead...

About 4 months ago (time escaped me while taking care of other things in life), my car failed to start. No warning, just starting one day and not starting the next day. I didn't even get the click-click-start,

I went through the usual suspects...

• Starter, OK
• Clutch Interlock, OK
• Security Relay (Replaced), OK

I was about to replace the ignition switch when I came across these articles; today I finally got around to jumping the relay.

Instant start. I can only hope now that my starter was sat least close to needing to be replaced and that was not a total waste of money.

Has anyone replace the starter sub-harness with a OEM Mazda unit (or rebuild it yourself) and had the problem resolved?

Prior to the non-start I was experiencing these symptoms:

1. Loud crackling noise from the radio, whether it was on or not.
2. No Odometer Readout
3. No Tach or Speedo.
   [*}ABS Issue - not related I think.

Is there a sub-harness that covers all these issues?

Whatever issues exist that were giving me all the above symptoms obviously still exists. Has anyone found a real cure - and not a band-aide (albeit a good band-aide)?

Sorry I did not get back... I let the car sit while attending other things - out on the road.

Thanks Adam, I assume you were speaking of the clutch interlock switch - I had replace that one and it did not solve the problem. Sorry I did not get back to you sooner.

 

No similar problems...yet. But you refer to reading some articles just before jumping a relay?? What articles? And this was the starter relay?

 

When I said articles, I meant various posts on this and other forums.


I believe the relay is known as the "starter security" relay. Changing it out did not fix the problem.

 

+1 for that. I had that happen to me and I fixed it that exact same way haha

I also had a issues with the click click start beyond the clutch switch button breaking out. I had tried jumpering the security relay to no success either. What ultimately worked for me was installing the starter "booster" aka a relay. Starter Booster, discussed here at post #24. I just bought a relay and did my own wiring for it and since I installed it have not had a starting issue since.

 

I jumpered the security relay circuit after I created this thread. The car had been good since then. Last night I went to the supermarket, came out and NO START.

Popped the clutch and took the car home. This morning, I crawled into the foot well and could see that the rubber stopper was gone. (Amazing how expensive getting the car home could have been for want of a rubber stopper if I wasn't able to pop the clutch.)

 

Holy Thread Revival!!!! lol. sorry, I just had to say it! Its amazing how something so simple can cause such big problems though!