RIWWP

iTrader: (2)

I cringe at the thought of towing it over an hour to the dealer, just to get hosed in the wallet there. You can expect easily over $1k, probably more like $2k+. If you aren't prepared for that, just don't get started down that route.

You may have to wait till Ash is awake (Australia), as he may be able to better direct you. I'm fast approaching the end of how much I can help.

BigCajun

iTrader: (1)

Hi, not going to hijack, but for clarification, do you unhook battery just for trickle charge, or any charging?

RIWWP

iTrader: (2)

Any external charging.

Every trickle charger I have seen has a warning "remove the battery from the car". I imagine there are chargers out there designed to be able to charge with the battery hooked up, for example the ones designed to install on the car so you can just "plug the car in" to keep the battery in shape. But those most likely have safeties wired into the car as well to prevent problems.

BigCajun

iTrader: (1)

OK, Thanks, had mine charging earlier & scared me a little. Sorry Fungster, hope it's not too bad. Good luck.

FungsterRacing

iTrader: (4)

I just read part of the testing procedure on the PCM, and unfortunately because the car will not start, I cannot perform most of the tests. On top of that I do not own an oscilloscope

Do you believe it is the PCM, or BCM? Even with the information you provided me, BCM is still a mystery. It does not seem to be a physical piece of hardware. It makes sense that if the BCM is bad, I would be having these issues, but I am not sure that I would also having no ignition, no normal sounds when the key is turned on, etc.

On top of that, there really is no BCM to test (As I have gathered, at least). Please correct me on any of this if I am wrong, but it feels like there could be a few problems

FungsterRacing

iTrader: (4)

Just talked to a Journyman tech out in this area, and he said his is 99.99% sure it is the Immobilizer unit that is screwed, as it would cause the car to be completely 'dead', but would still perform usual alarm functions (But that the constant on could be a result of a faulty unit)

Does that make viable sense?

RIWWP

iTrader: (2)

My mistake earlier, you are correct, I don't think the RX-8 has a BCM. I was probably thinking of a different Mazda model when I said that.

Page 6 of the PDF I sent you lists the modules, PCM, EPS, TCM, ABS, DSC, Keyless, TPMS, Steering Angle, and Instrument Cluster, so no BCM.

I wouldn't think that this is the immobilizer, as the immobilizer triggering would block ignition, but it does not block anything else. You would still have lights, OBD2 connection, etc...

FungsterRacing

iTrader: (4)

So BCM is obviously out the of question. It does have alarm symptoms (horn and park lights), but another possibility that I am thinking could be bad is the instrument cluster.

So the immobilizer bad would explain the lack of anything happening (engine wise), but as for the interior stuff, that still remains a mystery? As you said, the PCM has nothing to do really with interior things, so now I am stumped. Its hard to think that multiple things, such as the cluster and immobilizer are gone, but there are numerous problems that start at different sources...

RIWWP

iTrader: (2)

Would you be willing to make a list of what does and does not have electrical power?

I'm pretty sure there is going to be something common between the things that are without power. Possibly a grounding point?

FungsterRacing

iTrader: (4)

I will do, but you're going to love this. We pushed it into our workshop, and turned the key on, and what do you know, the instrument cluster lit up and the horn is no longer on.

Saying that, the hazards are now permanently on, and all most dash lights too, but the car will not start and I do not have interior lights nor does my deck or the led bar above it work.

So now this is where it sits:

Works:
Instrument Cluster
Fuel pump engages

Does not:
Interior lights or any interior accessories, such as deck and led bar. Door locks and Windows also do not work. Trunk unlock does not work.

Other Info:
Hazards permanently on
Engine will not even try starting
When you attempt to start, it clicks, but not as in the starter won't engage, sounds like literally a key click but under the hood

RIWWP

iTrader: (2)

Good information, especially the change. This is sounding more and more like a loose connection somewhere. Start checking every grounding point you can, in the engine bay (including under the air box on the frame) and under the dash.

Also, remove the battery and actually test it on and off the charger. Just in case what broke is something within the battery itself.

FungsterRacing

iTrader: (4)

On top of my above post (apologies if there has already been a response), the hazards go out after a few minutes. Everything else is as described above after hazards go out

FungsterRacing

iTrader: (4)

Again, the clicking when we attempt to start the car is not a starter click, it comes from above. And will start checking!

RIWWP

iTrader: (2)

Yes, the click you describe is one of the relays, which is good news since that is normal. The relay is firing correctly, just no battery power down to the starter from there.

At THAT point, yes, it may be the immobilizer, but that wouldn't explain the lack of any interior lights.

FungsterRacing

iTrader: (4)

Well the horn is going off like an alarm too, honking like crazy. It goes off eventually like the hazards, but takes a few minutes. So no interior power besides instrument cluster, and no starting. All relays are in working order as far as I can tell as well.

Might just be getting this problem fixed slowly...

RIWWP

iTrader: (2)

Thinking out loud...

There are 2 things that keep me from pointing at the immobilizer: 1) the lack of power to the interior lights (should be completely unaffected by the immobilizer) and 2) when the immobilizer is the only thing stopping you, you won't hear the relay click and you will have a flashing key light on your gauge cluster.

The hazards and horn fading after a few minutes DOES line up with the immobilizer's typical reaction of fading out after a while, although the immobilizer doesn't fire the flashers or the horn.

The thing that affects the immobilizer, horn, and hazards is the keyless access, for example hitting unlock/lock on your key.

From page 1 of the PDF I emailed you, the Keyless control module is in the lower right of the passenger footwell. I'd see if you can get to that and see if anything appears to be amiss with it.

FungsterRacing

iTrader: (4)

Wow that thing is a b**** to get at. Just figuring out how to get it out right now. So would the keyless explain the lack of interior lights?

RIWWP

iTrader: (2)

Hmm.... my gut says "no", but it actually does have a component of that. Like if you unlock the car, the lights come on for a bit, even with the dome light in the off position. They fade after a bit or after you insert the key into the ignition.

Might be on to something here...

FungsterRacing

iTrader: (4)

I'm hoping so. Still no 'key' or security light on the dash, ever. Here is where it sits:

Works:
- Instrument Cluster Illuminates
- Starter relay and fuel pump engage / seem functional

Does Not Work:
- Will not start (wont crank)
- No interior lights
- Trunk unlock not functional
- Door locks and windows not functional
- Deck, LED board and AC controls not illuminating / functioning

My keyless was slowly getting worse and worse over time, and eventually last summer it stopped working altogether. When the key is turned to ACC, dash illuminates, but no security light comes on. Hazards and horn reflect that of an alarm, and eventually go away. Headlights seem to work fine. All relays and fuses checked.

EDIT: When in ACC position, steering light is on as well. Not sure if that is normal, thought I would mention it. Can not get power from OBD2 either to check codes, it seems to not have power to it

RIWWP

iTrader: (2)

Hmm, I had forgotten about the OBD2 lack of power or signal.

Maybe there is a communication breakdown between modules? CAN network offline?

FungsterRacing

iTrader: (4)

Honestly, not even sure how to begin testing CAN communications But regardless, I am about to remove the keyless unit and go through the testing procedures to see if it is good. I'm actually hoping its not and that all my problems will be fixed... doubt it though lol

EDIT: Just got a little electrical schematic after doing some digging. Will soon be checking over the wiring to best that I can, if not I am thinking it could be anything at this point.

FungsterRacing

iTrader: (4)

Well I got the keyless unit out. Unplugged it, turned on the key, and the hazards/horn never went off, but everything else is still out as described above. This is so confusing lol. Still cannot get power to the OBD2, either. Checked all the grounds I could see under the hood, as well as one or two inside, all seem fine.

Was hoping that because the OBD2 is not being powered that it could be a Keyless Unit issue, but I removed what I thought was the keyless unit only to find out it was the keyless receiver - Apparently the unit has 2 connectors and the receiver has 3 (which is the one I removed from under the footwell - Can anyone confirm?)

FungsterRacing

iTrader: (4)

I want to thank RIWWP for all the assistance. One main problem has been found as in the process of being fixed. Everything was greatly appreciated.

It's amazing after reading through that online service manual and doing various tests on the PCM, Keyless Entry, Immobilizer, etc., that I have learned so much about how all of the components in the car work individually and together. I'll be sure to pass on what I learned to others.

FungsterRacing

iTrader: (4)

Problems persist:

Car now starts, but does not idle well and will not rev up. Pours a bit of smoke which smells of pure gas. Following codes: P0506, U1900, U0073. Now P0506 I am assuming could be a throttle body error, but I am not sure about the other ones. U0073 could mean any of the system modules

Does one think that taking it to the dealer, they would be able to quickly identify which module is bad?

RIWWP

iTrader: (2)

P0506 - Idle air control system RPM lower than expected. Until you figure out the communication errors, I wouldn't spend time hunting that one down. It's likely that the ECU is unable to figure stuff out correctly. The diagnostics for this is Engine -> Mechanical -> On-Board Diagnostics [ENGINE CONTROL SYSTEM (13B-MSP)] and there is a specific article for P0506 with that as the title.

The other two are communication errors that are linked. Too messy and too large to copy here, but there is a diagnostics procedure there for them in the workshop manual, go to Body & Accessories -> On-Board Diagnostics [MULTIPLEX COMMUNICATION SYSTEM] -> DTC U0073, U1900, U2516


Glad you are making progress!