sethbob3030

Ok, so I'm having some difficulty with my 2004 RX8 GT. A while back, (matter of months) I had to have my engine replaced due to what the local Mazda garage called a low compression issue. All I know in that regard is that when the car fouled up there was a severe lack of power, a lot of stalling, blinking CEL, and a "rough" sounding engine. Also, someone behind me claims that I shot flame out of my exhaust.

Now, having had my engine replaced (it seems to run great when it runs by the by), I am having some rather severe starting issues. Essentially, the symptoms are as follows when the issue occurs:

- First and foremost, there is a click that sounds electrical, almost like that click you hear when you turn the key to ACC.

- From there, I lose nearly all electrical power. No windows, no locks, no roof, no radio, no fan / temp control, no display on the radio, no interior lights, no key fob abilities.

If this happens while running, the only thing that stays on are the headlights and the dash lights, however I've noticed that here and there the dash lights turn colors as if I don't have my headlights on (from red to white).

Typically, if I shut off the vehicle and try to start it again I have none of the aforementioned items powered and the engine will not even crank when I turn the key.

It seems that very often if I wait at the very least 30 minutes or so and come back out, everything comes back.

The other symptom is that my radio stations are reset, and my trip mileage is reset to 0 as well after I finally get the vehicle started.

To list the number of potential solutions that I have attempted (and avoid some regurgitation of fixes) here are the attempts by the Mazda garage to date:

- Battery tested (just fine) and replaced (just in case)
- Alternator replaced
- Starter Relay replaced


I have read in multiple threads (none of which seem to relate too much to my issue or the fixes listed there do not work) something regarding a 120A fuse. If this is the fuse bolted down in the fuse box under the hood, upon visual inspection I will say that it appears to be fine.


Please, as I have limited discretionary income, it would be greatly appreciated if someone has some experience or may have a solid idea as to what is wrong.

Thank you!


PS

I apologize for not having the CEL code that has popped up from time to time when I have this issue, all that I remember is that it is a "Low voltage" CEL, I want to say P0420 but I am not 100% sure.

sethbob3030

As an update, I found that I saved the code in my phone - it is P0562 which apparently has something to do with low voltage. Hope that helps someone in the know so that I can -finally- solve this problem.

wrightcomputing

iTrader: (5)

If your battery and alternator are good I would guess you have and issue with the wiring.

Make sure all the connection are secure and free from corrosion. If you have a multimeter you can measure the resistance of the cables, then try moving the cable and see if the resistance goes up. Generally speaking the longer and thinner the cable the higher the resistance so check as many as you can and see if one seems abnormally high or fluctuates, if so replace it.

Also visually inspect all the cables and make sure no cables are trapped under something in the engine or have become damaged. If one of the cables have damaged/worn sheathing and metal is showing then it could cause than cable to ground meaning all your power is going straight in to your chassis.

Good luck!

Mazurfer

Disregard looking at the 120a fuse. If that was blown, you would never run at all and not much would work....ever.
To me it sounds like the laternator, but I see you've replaced that and the battery, so yes, it time to start looking at all the cables in earnest..................especially those coming off the alternator. If you have access to an autozone.....even though the alternator may be new, go have it checked again for free, or return to the place that you bought it(if you didn't do it yourself) and have them take a look at it(but have them do it for free).


Just an idea.................has anyone look at the igntion/key switch on the steering column? I re-read your symptoms and this came to mind.

sethbob3030

My hope is that it is not wiring, but I'm at that point where I suppose that I have to start looking into that. After replacing that starter relay, I have only had one instance of the car not starting which was perhaps 15 minutes after I left the garage, however within 2 minutes the car "reset" and was able to start. It's been roughly a week or two now with no issue, so hopefully that has been the solution.

I plan regardless to look into the wiring. Mazurfer, you mention starting at the alternator and working out, should I essentially just check every wire that I can find?

Further, you also mention the ignition switch, and that was brought up to me by the garage if I continue to have issues. What they mentioned as odd is that as you turn the key off, it catches. Being rather unfamiliar with Mazda, I was not sure if this was normal. I know as I am a car salesman that many makes have you turn off the key, then push in to take it all the way back and remove the key. Did Mazda not do this with the RX-8 in 04, and then this would be abnormal that it catches?

sethbob3030

The problem persists still. I have visually inspected as many wires as I can within the engine bay, cleaned all battery connections, checked as many of the grounds within the engine bay as I can. The only thing that I did notice that seemed a bit odd was a high pitched "hum" coming from one set of wires off of a connection to the air filter. The part number listed on this connection is N3H1 13 6B0 C. Not sure what it is, and whether or not the humming is normal or not. I'm hoping this may assist someone with some clue as to what the issue may be.

In mentioning the multimeter, I do have one, I just don't know what exactly I should be checking for and what I should be checking to narrow down the issue. Could someone provide some detailed insight into this?

viktor177

it might be bad connection on 120A fuse, try to take fuse out, clean connection, and put back in, or just replace it. I had similar problem, but fuse was blown, after replacing all interior lights, radio, windows, sun roof, remote start working. it might help in your case