The Honda PCX / Forza / ADV150 / SH Forums

It used to work perfectly, but today, I found idling stop sign light up, but engine doesn't stop.

anything to do with cold weather, or does it signal something wrong with engine or ECU or what?

It is normally the battery, at least on '14 reg onwards vehicles. The ECU disables idle-stop should it detect the battery is not up to the job, as idle-stop used to flatten batteries on pre '14 models. It's a staggered graph and not just volts/amps in a linear fashion.
You can charge the battery off bike but good batteries do not normally go wrong, even if bikes are left outside in the cold for weeks on end. Poor or failing batteries are one of the most common issues on PCX / Forza 125's (someome recently posted this issue in their 1 yr old Forza 125, and it was the battery)
Never found a use for idle-stop on 4 years of commuting - for the very little fuel saving, not worth using it imho.

iceman wrote:It is normally the battery, at least on '14 reg onwards vehicles. The ECU disables idle-stop should it detect the battery is not up to the job, as idle-stop used to flatten batteries on pre '14 models. It's a staggered graph and not just volts/amps in a linear fashion.
You can charge the battery off bike but good batteries do not normally go wrong, even if bikes are left outside in the cold for weeks on end. Poor or failing batteries are one of the most common issues on PCX / Forza 125's (someome recently posted this issue in their 1 yr old Forza 125, and it was the battery)
Never found a use for idle-stop on 4 years of commuting - for the very little fuel saving, not worth using it imho.

Well, My PCX is exactly 1 year old.
I think I should check the battery voltage soon.

I usually do periodic 20KM cruising in case it runs flat, and I never leave it out more than 2 days.
thanks.

iceman wrote:It is normally the battery, at least on '14 reg onwards vehicles. The ECU disables idle-stop should it detect the battery is not up to the job, as idle-stop used to flatten batteries on pre '14 models. It's a staggered graph and not just volts/amps in a linear fashion.
You can charge the battery off bike but good batteries do not normally go wrong, even if bikes are left outside in the cold for weeks on end. Poor or failing batteries are one of the most common issues on PCX / Forza 125's (someome recently posted this issue in their 1 yr old Forza 125, and it was the battery)
Never found a use for idle-stop on 4 years of commuting - for the very little fuel saving, not worth using it imho.

Sir, is there any chance the battery may run so flat that the system does not even start, which means leaving me amid mountains.

doletotodole wrote:

iceman wrote:It is normally the battery, at least on '14 reg onwards vehicles. The ECU disables idle-stop should it detect the battery is not up to the job, as idle-stop used to flatten batteries on pre '14 models. It's a staggered graph and not just volts/amps in a linear fashion.
You can charge the battery off bike but good batteries do not normally go wrong, even if bikes are left outside in the cold for weeks on end. Poor or failing batteries are one of the most common issues on PCX / Forza 125's (someome recently posted this issue in their 1 yr old Forza 125, and it was the battery)
Never found a use for idle-stop on 4 years of commuting - for the very little fuel saving, not worth using it imho.

Sir, is there any chance the battery may run so flat that the system does not even start, which means leaving me amid mountains.

Possibly - again, someone posted in the FB PCX/Forza pages this exact problem too - they got tick over but no start - took it to the dealer, problem was the battery. The '14 models and disable of idle-stop was to put an end to draining the battery in this way, as that is what used to happen. Not saying the battery is a dud but likely - it may pay to purchase a cheaper compatible battery first rather than pay dealer charges (if out of warranty). Stop using idle-stop is a good thing - it rarely does any good even on newer bikes - saves a few pence a month in fuel if that.

doletotodole wrote:

iceman wrote:It is normally the battery, at least on '14 reg onwards vehicles. The ECU disables idle-stop should it detect the battery is not up to the job, as idle-stop used to flatten batteries on pre '14 models. It's a staggered graph and not just volts/amps in a linear fashion.
You can charge the battery off bike but good batteries do not normally go wrong, even if bikes are left outside in the cold for weeks on end. Poor or failing batteries are one of the most common issues on PCX / Forza 125's (someome recently posted this issue in their 1 yr old Forza 125, and it was the battery)
Never found a use for idle-stop on 4 years of commuting - for the very little fuel saving, not worth using it imho.

Sir, is there any chance the battery may run so flat that the system does not even start, which means leaving me amid mountains.

Yes, there is a chance the battery can run flat, as happened to mine, twice. But the key with mine was I very rarely took it on a ride anything longer than 2 or 3 kms. I did not use the idle stop because traffic was heavily congested, requiring frequent stops. Both times mine went flat, someone else was using it with the idle stop.

Keep two things in mind about bikes and batteries.

1. No one can tell you how long the battery sat on a shelf before it was installed on the bike. Batteries by their nature are always working internally. Therefore, it is possible for the battery to be part way through its life expectancy before it is even installed.

2. Everytime a vehicle is started it draws a lot out of the battery...so much so that it takes about 10 miles of riding to recharge it back to where it was before starting the bike. Short runs with lots of starts and stops will drain a battery quickly. If that is your normal riding schedule, put the battery on a Battery Tender each night.

Even knowing these two things will not prevent one battery from dying before another, with both being produced at the same time. I carry a small jump start battery with me when I ride any distance from civilization. I have seen them for as low as $30 USD.

The constant use of the start motor may also be overloading the battery and not getting recharged adequately if not on a constant run. Lots of stops/ starts and not too much riding ???

If your run of the bike, and use of idle-stop seems to have affected the battery so much that your 2016 model disables idle-stop, it may not be a dud battery but the toll on the battery for your riding conditions is too great, hebce the ECU may have kicked in to allow the bike to work, albeit without idle-stop. Best stop using idle-stop, at least for a while and seems if idle-stop then works again - if so, either slightly dodgy battery or just do not use idle-stop.

Registered here specifically to respond to this thread. I found this link from Honda, stating that the idle stop, by design, is only activated when the engine is above 60C

https://global.honda/innovation/technol ... ebook.html

I originally couldn't work mine out. Totally erratic combinations of time of day, flipping switch before and after starting, working, no working... Given that beating the bike for ten minutes until the engine is up to temperature, and beating the bike for ten minutes until you've refreshed a depleted battery probably look very similar I thought it worth sharing.

I just tested by riding 12km home from work with it "not functioning" as per recent norm. Parked the bike and ignition off. Switched on again and rode a 100m lap of the carpark. Idle stop is working fine. Bikes only got 1000km on it so no particular reason to distrust the battery, or Honda's own website

Hope it saves lots of people buying new batteries! After about another 20,000km of riding it will have saved me enough in fuel to buy a can of beer.

Thanks for the input, bigred, and welcome aboard. My US'13 does not have idle stop, but like you, can't figure out how it can be worth the added complexity when the machine already gets 100 MpUSG. My guess it is there due to specific market/government regs according to your location.

Out of curiosity, could you add your ballpark location to your profile? Also looking forward to any and all comments and inputs you might share. Again - Welcome.

GeorgeSK wrote:can't figure out how it can be worth the added complexity when the machine already gets 100 MpUSG. My guess it is there due to specific market/government regs according to your location.

There isn't any added complexity, all the components required for it are present on the US version.
Rather than it being added because of regulations, the reverse is true.
Idle stop is not present on the US model because of the situation in the US.

No particular situation, unless you consider the general population's lack of taste for conservation a situation. "Myopic stupidity" and "willful denial" come to mind, but those are more mindsets than situations. My '13 was built before our current fearless leader, so the blame isn't there. Rather, idle stop just wouldn't be a selling point. Heck - being a scooter isn't a selling point around here.

I certainly can't explain my fellow countrymen.

For the record, I LOVE idle stop on my car, and will never buy another car that does not have the feature.