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About 6 weeks ago, my battery was completely proper flat. It's about 4 years old or so, Yuasa.
When it went flat, I hadn't driven it for about 5 / 6 weeks, so charged it with my CTek
Since charging the battery, I've only driven in once every two weeks I guess, but this time I don't think the battery can be saved this time.
Last few times I've driven it, the idle goes very low, and today I noticed the BV battery voltage on my PSi 3 has been fluctuating. I'm pretty sure that usually on idle, the PSi3 shows around 14 - 14.2 volts, even when idling - regardless of electrical load like wipers / lights etc.
The belt is tight / not squealing.
Does the below video I've uploaded show signs of the battery struggling and needs replacing, or perhaps the alternator? Both?
it's about 3 mins long, and a bit boring! But if you could have a watch that would be great.
The battery volts (BV) seem to actually increase a little when I load the battery up, but at times it's showed 11.5v approx with no load on it.
The car doesn't drive very nice, and sometimes idles so low it almost cuts out.
I'm not sure if BV is what's going into the battery, or what's coming out.
I've done around 160 miles in a week, and the BV is behaving as the video I made below :
About 6 weeks ago, my battery was completely proper flat. It's about 4 years old or so, Yuasa.
When it went flat, I hadn't driven it for about 5 / 6 weeks, so charged it with my CTek
Since charging the battery, I've only driven in once every two weeks I guess, but this time I don't think the battery can be saved this time.
Last few times I've driven it, the idle goes very low, and today I noticed the BV battery voltage on my PSi 3 has been fluctuating. I'm pretty sure that usually on idle, the PSi3 shows around 14 - 14.2 volts, even when idling - regardless of electrical load like wipers / lights etc.
The belt is tight / not squealing.
Does the below video I've uploaded show signs of the battery struggling and needs replacing, or perhaps the alternator? Both?
it's about 3 mins long, and a bit boring! But if you could have a watch that would be great.
The battery volts (BV) seem to actually increase a little when I load the battery up, but at times it's showed 11.5v approx with no load on it.
The car doesn't drive very nice, and sometimes idles so low it almost cuts out.
I'm not sure if BV is what's going into the battery, or what's coming out.
I've done around 160 miles in a week, and the BV is behaving as the video I made below :
[/QUOTE
When your fans kick in your voltage is climbing which indicates the alternator is behaving as it should. Does it start ok and how long before it goes flat.
I guess I drove it once a week or two, but wasn't slow cranking, starts fine.
Last night I checked the battery terminals, all tight, and with my volt meter the volts with engine off were 12.89v
This morning, checked the battery with volt meter, 12.69v and it started fine, went to about 1200 RPM when I started it, and BV on the PSI3 went to 14.2v
I can see the bright green dye through the battery sight glass on the top.
I'm stumped. I did have some loud beeps, which I think perhaps it was more of an alert that the bonnet was open, but I wasn't trying to lock it. I simply unlock it, pop the bonnet, then when I turn on the ignition I get the door / bonnet open warning beeps - different to the theft alarm sound.
I had this a few weeks ago, it's like the car thinks I'm trying to lock it with the bonnet up - I think it does this when I turn the key in the ignition.
I have no CEL, and the battery light on the dash goes out straight away upon starting.
The earth on the inlet manifold and on the inside of the wing near the battery are tight, and so is the nut on the power lead coming from the alternator.
I don't know where to start with my low idle, it almost cut out a few times yesterday, then the rev counter jolted back up to about 850 RPM
The car is drive by wire throttle.
Maybe the video above is because of the low idle I'm seeing the BV readings caused by the low idle, but what can cause such a low idle?? and then it creeps back up to normal RPM again...it's a bit like a cycle.
Something I've noticed, but could also be related - I've seen on a few cold starts that the PSi3 shows the letters and numbers in Japanese...it's not just random gobbledy gook like you sometimes see on an LCD display, it looks Japanese. Then suddenly goes back to English letters and numbers.
I wonder if the battery going totally flat several weeks ago gave the car the mother of all ECU resets?
It's a standard ECU and was mapped several years ago.
Last edited by Hawkeye D; 28 May 2023 at 06:13 AM.
When you re-charged your battery did you use the "recond" (recondition) option available on most CTek units?
How long did you charge it for? Did it reach position 7 on the scale?
Have you a battery tester to check if it's CCA value is close to or matches that quoted for the battery after it's been charged??
(cheap enough to buy on Amazon)
Quoted idle RPM in manual is 700+/- 100
generator/alternator info (yellow highlighted)
Your alternator is the same version as used for the MY08-14Hatch/Saloon models with the MY15 on models getting a 130A output version
Ah, didn't realise I had a recond option on the CTek...yes mine has that function.
I'll pop it on charge today and see what happens.
When I charged it several weeks ago, yes it went to 7 on the CTek, I left it charging overnight.
I feel like torching the car with aviation fuel to be honest!
Last edited by Hawkeye D; 28 May 2023 at 07:58 AM.
Yuasa usually comes with 5 years warranty, it could getting worst when cold around October. Mine is feed by aa solar panel, better that than get it flat.
New battery costs 65 quid,stop moaning for nothing.
That's odd, my current YBX5005 is CCA 550 according to the label sticker.
Found an old image from 2018 - CCA 550A back then
Having had my battery in the car on Ctek for a week, (Showing 12.6V on scangauge before startup), I took it out for a warmup and then recorded a short movie on tick over with A/C on. (attached)
Bearing in mind both the Hawkeye and MY11 Saloon use the same alternator (23700AA522) but different ECU's.
Last edited by Don Clark; 06 June 2023 at 12:02 PM.
Ah cool thanks Don. I'd say I'm probably losing about 3 or so volts on tick over - comparing the 2 videos.
I'm not sure though if the battery itself is my issue, or the alternator.
At times, the engine nearly stalls....particularly when reversing, then the RPM's jolt back up to about 850 rpm....would a shot battery cause that?
On a PSI3, I don't know if BV means what's going into the battery, or what the battery is kicking out?
A couple of observations... I haven't started the car or charged it in just over a week. Putting my multimeter on the terminals, I got at first 12.56v just over a week ago and now 12.10v
So it's holding charge? But....the green indicator ball seems to have dropped a good few inches...it's like it's at the bottom on the tube it sits in.
I noticed the green ball had dropped before I tried the CTek recond function, but the ball hasn't risen.
Battery Voltage is the system voltage with or without the alternator running so roughly 12-14 volts and is read via the obd port and ecu.
It's all connected
Have you seen this before? Your battery went from roughly fully charged to about 55% charged during that week.
I gave up with the green indicator a long time ago.
I believe the MY07 STi has a tracker fitted? so could add to the drain.
What I did notice in your video is that the voltage dropped dramatically to under 12v and took a long long time for the alternator to cut in and when it did, barely gets above 13.6v.
In mine as soon as it started at 12.6v (not shown in vid) it was over 14v in an instant and barely wavered from 14v. As I said before the a/c is on all the time with the fans running.
I get the feeling that your alternator regulator may be on its way out, but I would check all the wire connections and ground points first (especially the alternator mounting points which act as earths for the unit.
On the subject of batteries is the Yuasa battery a better option than the Bosch S4, my Bosch battery struggled all winter, it's 5 yr old and it's never been the same since it went flat after being parked up for a few wks so looking to get a new one b4 this winter, sorry to hijack the thread.
On the subject of batteries is the Yuasa battery a better option than the Bosch S4, my Bosch battery struggled all winter, it's 5 yr old and it's never been the same since it went flat after being parked up for a few wks so looking to get a new one b4 this winter, sorry to hijack the thread.
The Bosch S4-024 sits between Yuasa's YBX3005 and YBX5005 batteries, all of which are rated greater than Subaru's OEM requirement of 48 AH (55D 23L).
It all depends upon how you treat/look after it. (Keeping it above 40% charge (above chart), de-sulphating ( CTek reconditioning setting) at least once a year all helps to prolong its life.
On the subject of batteries is the Yuasa battery a better option than the Bosch S4, my Bosch battery struggled all winter, it's 5 yr old and it's never been the same since it went flat after being parked up for a few wks so looking to get a new one b4 this winter, sorry to hijack the thread.
Go for it Ted, we're all here for help, advice and information and to learn of other peoples experiences with certain issues.
I was a bit disappointed when someone on here told me to stop moaning about nothing, but it's a public forum so is what it is lol
On the subject of batteries is the Yuasa battery a better option than the Bosch S4, my Bosch battery struggled all winter, it's 5 yr old and it's never been the same since it went flat after being parked up for a few wks so looking to get a new one b4 this winter, sorry to hijack the thread.
Thats the problem, once any battery goes flat they are never the same ive always used the Bosch s4's without issue although mine went flat and now id call it a lazy battery - you can hear the difference in starting.
I'm not sure if a duff battery would cause my idling issues though....
If it can start the car, I can't see why it would idle really low then ping back up to 850 rpm
Starting the engine is easy as both + and - terminals are vitually connected direct to the starter.
It is possibly the ECU receiving bad / unstable signals or poor earth returns
Check the ECU earth terminals on the top of the inlet manifold, the battery - terminal to inner left wing earth, and make sure the inlet manifold to right wing link is in place.
ENGINE GROUNDS RHD DOHC TURBO MODEL
And maybe examine the Engine loom to bulkhead loom connectors E56 and E3 for dirty connections. (shown on both wiring diagrams above.)
Thank you very much for that Don, gives me more depth to check into.
I've not seen the battery light on the dash whilst driving.
I'll check earths / connections E56 / E3 first.
Replace battery, then fingers crossed.....last resort regulator.
TBH it wouldn't hurt to get a new battery after the few recent full discharges it's had.
I was told connect a normal stop light bulb between the battery connector terminal and the clamp/ lead , then the time consuming part , pull one fuse at a time until the bulb goes less bright and that’s your source of the battery drain , a tail light bulb with minimal battery drain will be on but not as bright as fully lit up 👍😁
I was told connect a normal stop light bulb between the battery connector terminal and the clamp/ lead , then the time consuming part , pull one fuse at a time until the bulb goes less bright and that’s your source of the battery drain , a tail light bulb with minimal battery drain will be on but not as bright as fully lit up 👍😁
Yep thats the way to do it one by one on the fuses but a cheap multimeter is better than a bulb...at least with meter you have a voltage reading to go by
27 May 2023, 09:44 PM
Battery voltage issue?
ive always used the Bosch s4's without issue although mine went flat and now id call it a lazy battery - you can hear the difference in starting.
