I dissected my broken SSU. There was nothing obvious wrong visually with the PCB components. The on-board relays and motor all worked when a 12v feed was supplied. I’m too fairly sure it was a mechanical issue, but it’s impossible for me to say as I had to drill through the lock tenon to remove the unit. In the UK I think a new SSU is £480 + VAT
£480 + VAT, my God… It’s almost my (lousy) monthly retirement pension in Poland. @mx5IOW please tell me - was yours also intermittent and temperature-dependent?
Intermittent, yes. Didn’t notice it being temperature dependent. The grease in my unit looked the same as in the Youtube video - It doesn’t look good, but in reality it’s OK.
My symptoms were different to yours - I had the beeps and flashing orange on the start button, but my car wouldn’t start as the steering lock wouldn’t disengage regardless of banging/waggling the steering.
My ThinkCar code reader didn’t show any fault codes. However, there were numerous historic SSU fault codes showing when it came back from Mazda - I assume these were from when the unit failed totally - I think maybe it blew a driver chip from the lock being continually mechanically stuck.
I bought a used unit (Same part number) on ebay complete with the steering upper column for £30.00, but it still had to be configured by a Mazda dealer (As would a new unit).
Sure thing…Gotta love today’s cars! I remember when - being at my best 20s - I single-handedly replanted the whole engine-clutch-gearbox assembly to my Polski Fiat 125p, which - originally with just a 1.5L engine - wasn’t poweful enough for me (BTW the engine I planted-in was also from Fiat, the 2L 132 model - and the tine difference of 75 vs 115 PS was a goal worth enough for me. Nothing needed to get registered/configured after the swap; pure joy of an analog car of 1970s!!!
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I’d like to ask all the participants of, and the lurkers into, this thread: if your experience with intermittent failure of the steeering lock system is the same as mine and @mx5IOW’s and you DID get the Mazda diagnostic computer connected:
has the computer shown any concrete and relevant error codes?
Asking because - trying to make to total cost of repair, should I decide to achieve it the most official way, and strongly suspecting a purely mechanical nature of the problem - I wonder whether or not I should do my best to avoid the high initial cost of the Mazda authorized repairer’s proceedings by asking them to bypass the diagnostic computer use and going straight to disassemble the Start Stop button subsystem and searching for some potential reasons of such a malfunctioning. Of course I realize the Mazda computer will have to be used on the later stages of diagnosing and repairing the system.
As the OP, I’d also like to apologize for allowing the thread to evolve in a different direction that its Header would imply. However, this is not a total change of the subject; those five double beeps AND the intermittent steering lock failures might be drastically different results of the common reason:
stamina-lacking battery
I DO have my very specific reason to suspect the battery as the ultimate source of both anomalies discussed in this thread; however - even though it’s very interesting, and cost me a lot of problems during the entire Warranty period (the battery was replaced 4 times in the years 2019 - 2023, and yet the anomaly I mean has never been gotten rid of - I will refrain from describing it just yet… Will do so definitely, but probably in a separate thread with appropriate heading.
Cheers,
Piotr
Unfortunately those days are long gone!
At least Mazda ‘allows’ the use of used modules to help keep the repair cost down. Many manufacturers VIN lock modules, forcing you to buy a new one…
FWIW, I had the authorized Mazda shop diagnosed my car. Even though the steering lock was working properly on my appointment day, the diagnostic computer found the error code (96, for DTC B1026 - status 8A) stored in the memory. Also, using the testing procedure (locking/unlocking many times) it was able to re-create the 96 code. Unfortunately, the only solution the shop offered was replacing the entire START STOP UNIT - for a price I’m not in position to pay right now 
Also, they replaced the secondary immobilizer battery which solved my “warning beeps” problem (even though I had installed what was supposed to be a fresh battery just several months ago). All in all - even though the issue being mentioned in this thread’s header has been resolved - the amount of cash I left there for diagnosing - but not solving - the much more serious problem is rather frustrating…
Thanks to everyone, nonetheless
Piotr
2 Likes
Secondary immobiliser battery?
What/where is this?
Hi @ChesterDog;
I don’t know about the US or UK Miata, but here in Poland (and possibly in the whole EU) Mazda MX-5 comes with the thin, rectangular, black plastics box attached to the main key fob. Inside there is a 3.3V battery identical to the one inside the fob. Of course when my steering lock problems begun I replaced the sais battery with a fresh one.
That said, it’s funny that you mentioned the immobilizer thing, because as of just yesterday I witnessed a development here having much to do with it. My steering lock went unresponsive again right after I had it “diagnosed” at the Mazda authorized shop (for a hefty price); I was sitting in my car last morning watching this yellow warning light on the S/S button and playing with the sequence of things we normally do before starting the engine in hope to do something different enough for this yellow light to turn green upon depressing the clutch pedal, when - low and behold - something extraordinary happened:
- when I depressed the clutch WHILE touching the S/S buttonn with the immobilizer box thingy, the green light came on as it should, and my steering lock system became fully operational!
I have performed many start/stop cycles ever since and the locking system is still working properly both ways (locking when I get off and unlocking when I set off). So - since the Mazda shop’s incompetence has been obvious, and they charged me for nothing - I’d like to expand my knowledge to be solid enough before I return to them and ask for refund (or replacing my immobilizer unit free of charge as a minimum). To this end, I’m kindly asking those of you more knowledgeable than myself to help me and answer the following:
1. Do your Miatas come with this extra box attached to the key fob chain (which Mazda Poland call “secondary immobilizer”??
2. Could you please find and share with me a relevant repair handbook fragments (2019 ND2 model, B1026:96-8A-SSU error condition)?
I’d very much appreciate your help, as without having a deeper understanding of the situation I won’t be able to even engage those guys in a discussion - not to mention convincing them they don’t know what they’re doing. Because - let’s be serious:
- Mazda has charged me almost GBP 200 for merely hooking up the computer to my car, and their advice was to pay them GBP 1,000+ for replacing the entire SSU
- it’s enough to touch the S/S button with the immobilizer box to make the problem go away!
Piotr
I see. Thank you.
UK and US MX-5s don’t have that device.