Townace NOAH CR42 /Indicate check engine bulb/p1123 error code

[kayman]

I have a Toyota Townace Noah CR42 van manufacture in 2003.There have a fault indicate check engine bulb on traffic.At that time accelerator not respond normaly.So however I scanned this vehicle and I got P1123 error code.So mechanic check the throttle body sensor and clean it.Then he said its not have any fault.So I cleaned the diesal tank and newly use d. filter.clean there accelerator paddle sensor plugs.so still I have a problem with check engine bulb.After that all mechanic opinion is add a new Throttle Body Sensor.But he isn't have any idea where fault comes from TBS,APP or not.So what should I do?I check another place and he also got P1123 code and he also not have a any idea which part have a fault.("sorry about my english. 😁")

[iRage]

Well a quick Google search suggests a 1123 can be from a Throttle Position Sensor or a Coolant Flow Sensor in some vehicles. Does the TownAce have a Coolant Flow Sensor?

How much is a TPS ? If it is not too expensive you might as well change it and see what happens? I suppose it will be difficult to find a sensor temporarily just to check it.

[kayman]

On 11/24/2025 at 7:53 AM, iRage said:

Well a quick Google search suggests a 1123 can be from a Throttle Position Sensor or a Coolant Flow Sensor in some vehicles. Does the TownAce have a Coolant Flow Sensor?

How much is a TPS ? If it is not too expensive you might as well change it and see what happens? I suppose it will be difficult to find a sensor temporarily just to check it.

No.there haven't Coolant Flow Sensor.I check the price in some places,there prices 20-30,000lkr.Yes,I'll change the TPS later.Thank you. ❤️some guys told me clean Thermol and EGR.Before I should check these before I mentioned and later change TPS.What do you think clean thermol and egr is help to fix this problem?