DRCC Fault -fails to regain speed

[2Nick]

I have a 2023 Icon 1.8 Hybrid Tourer. The DRCC works fine when tracking vehicles ahead moving at a relatively constant speed.

If the vehicle ahead slows enough that DRCC has to slow my vehicle by decreasing the throttle into the charge mode it then just goes to "idle" and does not increase speed when the vehicle ahead speeds up. If I do nothing my vehicle just slows as if its just idling. If I quickly tap of the accelerator peddle it restores normal behaviour and the car speeds up to the set speed and maintains it as expected.

It also shows the same behaviour when descending hills, if the DRCC slows the vehicle when you reach the bottom of the hill the vehicle fails to accelerate and would coast to a halt if I did nothing, again a small tap of the accelerator peddle restores normal behaviour and the car speeds up to the set speed and maintains it as expected.

I have been to the dealers and they could offer no solutions and checked all settings.

I took out their demonstrator and this worked perfectly I spent 2 hours trying it where my car would have misbehaved and the demonstrator coped with all scenarios.

I would also add that I had a 2019 hybrid tourer for the previous 4 years which worked perfectly so I am used to how the system is supposed to work.

Any one else seen this behaviour?

[Cyker]

Can't say I have, although I usually disable the DRCC when traffic ahead slows because mine handles it really badly, so I don't have as much experience.

Maybe the system needs a firmware update?

What following distance have you set? Does it change the behaviour if you set it to minimum distance vs maximum?

[2Nick]

Ive tried all the distance settings and been through all the other Safety Sense settings like PDA etc turning them on off with no change.

When tracking correctly it works very smoothly as did our previous corolla which makes this all the more obvious and dissapointing.

Im thinking a software bug or an intermittant conection , badly aligned or loose camera, it seems to be set very low in the apparture We had one instance for about 30mins when it seem to work ok but then went back to this behaviour when restarted.

 

 

[Cyker]

Hmm, can you compare the camera position to another car? Maybe it had a new windscreen but the ADAS pod wasn't fitted properly or it wasn't re-calibrated?

It would also be worth getting them to update it all to the latest firmwares just in case - It may have been accidentally reset to the original at some point; A user on here had that happen to them which caused their 12v Battery to drain and they missed this several times before someone there finally thought to check the versions.

 

[2Nick]

yes I think thats a good idea. unfortunately the dealer I bought it from is losing thier Toyota Franchise this month and isn't really interested. They assure me they will do do a handover so hopefully the new dealer will play ball.

going to disconnect the 12v Battery this weekend and hopefully reset and restart everyhing -the good old switch off switch on again! ... you never know

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[JasonM]

Some while ago Nick but did you ever resolve your problem as I have the exact same issue?  

[2Nick]

2 hours ago, JasonM said:

Some while ago Nick but did you ever resolve your problem as I have the exact same issue?  

Hi Jason yes  the new dealer (Snows in Poole) had Techs who were good, willing to talk and work it through. It turned out to be the Accelerator pedal  assembly I believe there was intermittant contact on the position sensor. I found putting  side pressure on the pedal briefly would make it work until I switched off the car. I could stop it working by a quick kick of the  pedal in opposite direction.

They swapped out throttle pedal assembly  ... problem solved!

 

 

[JasonM]

That’s interesting Nick many thanks for picking this up again.  I thought it would be more likely to be the brake pedal position sensor if it was interrupting the cruise control and hadn't considered the accelerator pedal sensor.  I have taken my car to the dealer once already but made the rookie mistake of letting them take the car out themselves and they saw no problem.   I will take it back again and demonstrate the problem myself as seems easy to induce the faltering of the cruise control catching up a slower car running downhill.  I wonder if it’s gravity acting on the pedal that means the issue is mostly downhill, I will experiment by trying to lift the accelerator pedal whilst on cruise control and driving down a gradient.   Thanks again.

[Cyker]

Thanks for letting us know; I'm impressed they were able to diagnose something like that as it sounds quite obscure!!