[Rubb]

Hi everyone,

I have a problem with two fault codes in my PEUGEOT 307 1,6 HDI 2007.
P0121 and P1531, P0121 need to be resolved in 1 month or I am not permitted to use the car.

Fault codes:
P0121 - Throttle Position Sensor/Switch A Circuit Range/Performance Problem
P1531 - Invalid test - Accelerator pedal movement

If I have found the correct meaning for the fault codes.
I guess that these two codes are connected, my guess is that the position sensor from the throttle(s) are giving a value that does not agree with the data map.
I did reset the codes with an OBD-2 instrument. Did not use the car for a few hours and then after I had used it later that day P0121 was back.
I did reset it directly when I came back and went for a ride when the engine still was hot and the code has not come back again.
So it is hard to know what is triggering the fault code.

What I believe is a throttle:
Delphi No. 9657485480 or 25378171REV
It looks like it has two throttle actuators, one that can bypass the intercooler (used for cold starts maybe?) and another one that is located after the intercooler.

Anyone that has any experience from this fault code on a Peugeot 307?
I'm thinking of buying PRF 7-78 contact spray and just use it on the contact I believe is for throttle control, or is it just a waste of money?
If someone suggest using oscilloscope on the contacts for the throttle, if someone has a schematic for the contact would be awesome

Sincerely,
Rubb

 

[Gibbo]

Planet or Diagbox can test the throttle position.

http://www.peugeotforums.com/forums/general-discussion-2/how-contact-member-peugeot-planet-diagnostic-28190/


http://www.peugeotforums.com/forums/introductions-28/brief-faq-guide-new-members-83170/#post529130

 

[Rubb]

Thank you for your reply.
It would have been a great tool to have, not sure that I will have it delivered before the deadline for the new inspection.
Checked the PP Map, but Sweden isn't the best place for that
So, I guess I will have to leave it to a Peugeot dealer to have it fixed this time.

 

[reliable406]

Diesels dont have a throttle the throttle position sensor it mentions IS the accelerator pedal

The actuators you are talking about are not anything to do with controlling engine speed they just control air through the intercooler or not and are used to strangle the engine when you turn off they do not move with the accelerator pedal like a petrol one does.

 

[Rubb]

Thanks for your reply reliable406,
I will look into the accelerator pedal.
Anyone having a schematics for the pedal? Would have been nice to measure what kind of response the sensor gives, I guess it is just a potentiometer.


I know that the usage for a throttle in a diesel is not for the same reason as for a gasoline engine. Just did not know the name for it and the delphi part number just gives me results for "Throttle body"
I guess that it also could be used to lower the intake manifold pressure to increase the pressure drop between exhaust manifold and intake manifold for the EGR flow.
But if that actuator is not connected to the P0121 fault code it is just one less thing to check

 

[reliable406]

Yes they are used as part of the EGR system and during regens but i was being simplistic

Accelerator pedals are 2 potentiometers in reverse 1 counts up other counts down and the ecu uses both readings as a failsafe it compares them to be sure its right but i would be looking at the wiring too as a lot of problems are really wiring rather than the parts.