Vsc brake system p400 code

[Tomm5]

Still have trouble with my 2012 avensis d4d dpf model with code p400 tried most things cleaning egr valve and put new Battery in fault will clear for day or two then will repeat again any ideas lots people seem have this fault too

[Devon Aygo]

I assume the code should be P0400? The car will have an EML light on the VSC message/light is a secondry issue caused by the P0400 code.

P0400 is a Exhaust gas flow issue:

The EGR system recirculates exhaust gases. The recirculated gas mingles with the intake air so that the EGR system can slow combustion speed and keep the combustion temperature down. This helps reduce NOx emissions.

In order to increase EGR circulation efficiency, the ECM adjusts the EGR valve angle and the throttle valve angle.

P0400 (EGR valve malfunction)

DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
After warming up engine and idling for 60 seconds, maintain engine speed at 2500 rpm for 40 seconds, drive vehicle, and perform engine brake deceleration by fully closing accelerator when engine speed is 2000 rpm or more.	The target and actual positions of the EGR valve are different for 40 seconds or more. (1 trip detection logic)	EGR valve stuck EGR valve does not move smoothly Open or short in EGR valve circuit EGR valve deposit ECM

 Has the EGR been blanked off ?

There is also a lot more to the EGR system than Just the Primary EGR valve ( see pic attached ) and a blockage can be further back in the circuit, the gas follows the blue arrows passing first through the EGR cooler ( yellow ) then onto the secondary EGR valve ( green ) then through the cylinder head before coming to the Primary EGR ( red ) and finishing in the intake manifold.

[Tomm5]

Thanks for quick reply no it's not blanked of had car for first year no problem with car then got car service in Toyota got rear pads changed one day that popped up on dash so bought code reader and that code came up I can erase the fault but it come back drove car on motorway seems to trigger of dash lights when car gets very hot so may be blockage somewhere along system  I think.