Unexplained 1.33 Stop Start Behaviour. Anyone Else Notice This.

[Mooly]

I did post on this a couple of months back but thought a new thread was in order.

I suspect not a fault, but either a software glitch, or that perhaps something is being monitored and the "conditions are not right" at the time this happens. Last week this happened.

Can anyone explain why I could drive 12 miles or so on mixed roads, urban, sub urban and dual carriageway and not once during several stops for lights, roundabouts etc did the stop start kick in.

On the return journey after being parked for only 20 mins or so the same happened... it didn't operate. Every time I pulled up ECO OFF illuminated on the dash. Well into that journey I manually turned OFF the eco mode off and then turned it back on some miles later... still no good.

Some two miles from home it suddenly started working and worked for the next couple of times untill journeys end.

Before this episode it had on odd occasions done this, but for some strange reason a quick high rev blast always seemed to reset it... but not this time. The return journey included some 4 or 5 miles motorway where I deliberately used both 4th and 5th to give it a little hi speed run (with no effect). For a few weeks up to this last occurence it has been fine, and it's been fine since.

Software glitch maybe ?

[Parts-King]

My Urban Cruiser always stops if conditions are right so I suspect you maybe have a problem, get it booked in to find out. I doubt it is software related, more likely something mechanical is not working/set properly

Kingo

[FROSTYBALLS]

Doesn't it depend what electrical load the car is under, as to whether the stop start works. I.e air conditioning, etc.

[Parts-King]

Doesn't it depend what electrical load the car is under, as to whether the stop start works. I.e air conditioning, etc.

Yes it does but even with A/C on, the car will stop for a minute or so and then start back up on its own

It could be something quite simple such as the clutch switch not set correctly

Kingo

[Mooly]

Hi Kingo and Frosty,

I will ask next time I'm at the dealers (our Corollas due service and MOT shortly) and see if they have had any comments.

It seems to "know" that ECO mode is triggered as the "ECO OFF" illuminates on the dash as soon as you take your foot of the clutch when stationery, it's just that the engine doesn't stop, in fact just like when the engine isn't up to temperature and ECO won't kick in by design.

Just done similar journey today and it worked every time. If I find anything out I'll post it here.

[Kwazii]

I don't know if you ever got to the bottom of this, but yesterday I test drove a 1.33 Auris TR and the dealer mentioned it won't come on if below a certain temperature (4 degrees next to a sensor) and also if the Battery has less than 75% charge.

[adamc260]

I've noticed with the 1.33 sometimes if you dip the clutch say in traffic, the revs will drop quite low (like under 500) and bounce straight back up, almost like its about to stall but it saves itself!

[Mooly]

I don't know if you ever got to the bottom of this, but yesterday I test drove a 1.33 Auris TR and the dealer mentioned it won't come on if below a certain temperature (4 degrees next to a sensor) and also if the battery has less than 75% charge.

Not really is the simple answer... although temperature does seem to have a lot to do with it. I find if you turn the climate control off then the stop/start works even at low temperatures and before the engine is anywhere near fully warmed. The dependance on the heater settings is major annoyance and to me, given all that is programmable these days, should allow a little user input. When the S/S does operate in cold weather it's only stopped for perhaps as little as 8 seconds before it restarts... which is useless. Why not have a user switchable option that allows the heater to turn off when the S/S operates. The compressor for the A/C adds another variable into the equation. In "warmer" weather and with the A/C on... and I drive with it permanently on... then the S/S never stops for more then 25 seconds. Turn the compressor off and it will stay stopped. Why ? Is is too prevent thermal cycling of the evaporator ? to stop the windows misting as the blower then feed all through a wet evaporator that isn't cooling ? I don't know.

Bottom line is it's a flawed system too me, but one that given a little user input could be made so much better. That said I have clocked up over 7 hours in ECO mode in 10 months and 8.5K (engine off) and that's with a max of 25 seconds stopped. If it stayed off for longer that figure would be much higher.

[bruce e]

Check page 218 of your handbook, it lists the circumstances when the stop/start will not operate.

If you have an automatic aircon & you set to demist then stop/start becomes inoperative, as it does if there are repeated stop in a short distance etc etc

[Mooly]

Thanks bruce e

Haven't looked but I will when I remember :)

Today it's worked OK, temp showing 3C although it only stays off for around 6 seconds or so with the heater on.

[FROSTYBALLS]

The stop/start on mine worked several times this morning on my way to the office - external temperature showing minus 3. Had the radio and heater on (but not in automatic mode).