Jastreb

iTrader: (1)

Hello good people of RX-8 club, I would appreciate any tips you can give me to help me bring my poor RX-8 back to life.
Background:
Two years ago I moved to Michigan and when I did, I inherited a 330i which became my daily. Consequently, the RX-8 spent long period of time sitting in my garage, but I would drive it every couple of weeks. Last November, I left for a week for Thanksgiving, and when I came back, the battery was completely dead (it was not dead before leaving). After re-charging the battery via battery tender, I tried starting it and it refused to crank with a rapidly blinking immobilizer light in the instrument cluster. Since I had another car to drive I had put off serious troubleshooting until now. I have checked all the fuses (they all tested good) and recently put it in a fresh battery. Battery terminals are original but are clean.

Up to the point that it died, it had been slowly accumulating electrical faults. First, the ABS light came on (even before I left California), which was diagnosed as right front wheel speed sensor, but replacing the sensor didn't fix it, and later a problem with the left front appeared as well. More recently, the TPMS stopped working, and the last few times I drove it, there was a misfire starting at 4000 rpms. Now, these problems all could be unrelated, but I figure I should mention them as you will see evidence in the DTCs.

Problem Description/DTCs:
CEL is on, and when I read the codes via my OBDLink LX + phone app, only U0167 (Communication error to keyless control module) comes up. When I finally downloaded the free version of VersaTuner and hooked it up via the OBDLink, there are a bunch more codes, which I will list in order of supposed relevance to the immobilizer problem. Descriptions are based on what I have gleaned from the workshop manual.

P1260 - Immobilizer system problem (VersaTuner description: Anti-Theft System Signal Detected - Engine Disabled)
U0167 - Communication error to keyless control module. It looks like only the PCM can throw this code.
U0155 - Communication error to instrument cluster. Can be thrown by the the PCM or the DSC module.
U1900 - CAN system communication error. This looks like a generic code than can be thrown by several different modules.
U2023 - Abnormal message from other module. Several modules can throw this, but if it comes from the DSC, power steering or immobilizer modules, it means "Abnormal message from PCM".
U0127 - Communication failure between instrument cluster and TPMS module.
U2064 - Warning light illumination request signal from other modules. To be expected, since the dash is lit up like a Christmas tree.
U2617 - Wheel unit No.2 (No response). TPMS - consistent with earlier TPMS problem
B1318 - Power supply low voltage. It looks like this can be thrown by a bunch of different modules, but consistent with the battery being low earlier. (Although shouldn't have all the old codes been cleared when I replaced the battery?)
C1145 - RF ABS wheel speed sensor
C1233 - LF ABS wheel-speed sensor/ABS sensor rotor system
C1306 - Steering angle sensor not initialized (expected after battery disconnect)

So, it looks like a bunch of my modules are alive but not talking to each other.... I know the keyless entry/immobilizer is alive because I can lock/unlock the doors with the remote. All the accessories (stereo, wipers, lights) also work. I wish there was a way in VersaTuner to see which CAN-bus codes are being thrown by which module. Any ideas or suggestions? Did some data get corrupted in the immobilizer? Is the PCM fried? Did a rat chew my wiring harness?

I am thinking of having it towed to the dealer in the hopes that it's an immobilizer issue, but I have very little faith in dealers' abilities any more. I am afraid they will just start throwing parts at it at great expense to me. The only other thread I have found with a similar issue is olddragger's from years ago, and that didn't end well for the car
Thank you in advance for your input.

Loki

iTrader: (1)

What year is the car? Do you have another set of keys you can use? With at least one working key you can reprogram the others, but without any working key you'll need the dealer.
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I'm a bit surprised all these codes appear without even driving the car, suggest you clear them and start fresh.

A rat chewing on stuff cooooould cause some of these, but I would be surprised, they don't selectively chew on canbus wires and everything else appears to work right? Either way definitely inspect for damage, especially behind the glovebox.

BigCajun

iTrader: (1)

You could try this DTC diagnostic troubleshooting that gives you flashing code directly from the car.
Maybe the same thing you already saw, but maybe it will pinpont the main problem.

https://www.rx8club.com/series-i-do-...utputs-155947/

Skip down to the immobilizer section.

ASH8

Agree with Loki..
You have a Series 2 R3, post above mine is for Series 1 RX-8 Trouble Codes, they do not all match exactly as S2 has a different Immo and many other electrical hardware.
Looks to me like you may have RATS chewed through main harnesses??
Take off negative battery terminal for about 30 mins to drain residual so all DTC are reset, reconnect and Start car again, drive if you can. Take another reading as this will be your accurate one.
In S2 the only thing in Immo I would look at is your Key Fob Battery do you see a light when you press on a lock button, if not renew coin battery until you do, plus Battery contacts in fob go flat with age and it helps to carefully raise them up about half a millimeter, then re-install new coin battery..

BTW, Steering angle sensor one should go once you turn steering wheel from left lock to right lock and back center and then turn car engine off and then restart will reset ABS.
Are your tire pressures all good, are they factory R3 rims?

S2 Immos have been very reliable, any other electrical mods to car?

Frankly you need a Dealer to hook up to Mazda IDS, I don't trust any another scan OBD tool, unfortunately a process of elimination as trying new parts is all you can do in many cases.

get back

Jastreb

iTrader: (1)

Thanks for the replies. The car is a 2009 with advanced keyless entry. I have 1 working key (I can lock/unlock the car without a problem). The 2nd key doesn't work (I lost the key part from the card).
I cleared the codes as you suggested and 6 remain:
U0167, U0127, U1900, C1145, C1233 and C1306. I don't think the last 3 are particularly relevant... I can't drive or even start the car as it refuses to crank.

U0127 is for the TPMS, but from the workshop manual, it seems that TPMS signals are handled via the keyless control module?

Three years ago, I had some rats get into the ventilation system and make an acorn cantina in my cabin air filter. But I cleaned it out and didn't have any immediate electrical issues, though the wheel speed sensors started acting up several months later. The only electrical mod is an oil temperature sensor. Unfortunately I am in the middle of moving my household, so don't have much time to troubleshoot. Need to make a decision on whether to tow to dealer or to new house...

ASH8

Look I seriously cant remember, too hard for me at the moment, but...
I don't have AKE thank goodness as they are a POS, Mazda did not sort it out until Gen 7 Models from around 2019, much better set up.

Anyway I recall if you do not have the emergency key actually mounted in the FOB Card it can throw DTCs, I know it does on Gen 7 cars....not certain on S2.

looks like Dealer visit.

RastaRx-8

sounds like a PCM fried to me or has been replaced with a series 1 ecu by someone on accident who knows. for sure try clearing all these codes and see what is "continuous" only then go from there. Also poor grounds under the dash is my second guess because thats where almost all of that grounds. these cars are very particular on the can connections cooperating together so it may just need the right ABD (as built data) flashed in with forscan. i cant remember if you can see it with versatuner or not i had both.

Also the key issue does not require a dealer ever thats what locksmiths are for you just need to call one that services ford or mazda. i called the ford dealership after zero cooperation from my mazda dealer and that guy said he had a guy that could do anything and he was right. They have to have the IDS though , yes. but i paid 200 for my PCM programming and two keys made (AT to MT swap)

ASH8

Jesus, No it is impossible to Install a S1 ECU into any S2

RastaRx-8

is that a challenge? lol

also the valet key in the smart card button remote is what has the chip and is required to start the car. if thats not in the remote it will not start.. does not throw any DTC's its like tryin to start any car with no key chip it just flashes (yes the flashes will tell you the issue with the chip not being present but it doesnt activate any permanent codes)

Jastreb

iTrader: (1)

I had her towed to her new home today



This week have been busy moving all my stuff to new house, so no time to troubleshoot further, but I think I will start with the keyless control module harness. Local dealer doesn’t have appointments available for next 2 weeks anyway, so might as well see what I can figure out.

I am the original owner, so I know the PCM is original proper series 2. The codes that re-appear after clearing indicate PCM is ok, but immobilizer is not communicating. Good to know about the 2nd key fob needing the key part. I have been trying to start the car with my one good remote.

Also need to pump out the old gas and replace with some fresh gas before I take it to the dealer. Oil is about 2 years old as well, but I’ll worry about that once she’s back to life.

VanHilwen

Any update so far? My 2006 rx8 is starting to have the same issues, only difference being I can still start and drive mine with an extreme power cut at 7000 and then the stability control light comes on. When I tried scanning it out the engine into anti theft but I cleared it out and started it with the manual key.

airman3221

Hey! I wanna know what happened in the end since I'm having similar issues (U1900). Any updates?