NEED a little help here from the experts!

Guntar13 · Post by **Guntar13** » 12 Oct 2017, 17:19

Ive got a 2003 S80 T6 that I'm currently working on and am having trouble with some diagnosis of a problem. Ive got three OBD codes showing up that I am chasing and don't want to be a parts slinger! Ive got P0573 (should be the brake switch on the MC), P0447, and P2400. More than likely the 0447 is the one causing the code for the 2400 but I'm getting a bunch of conflicting information about what causes this code and more importantly what the fix could be? any help pointing me in the right direction is much appreciated, thank you guys and gals!

Post by **precopster** » 13 Oct 2017, 05:45

Do you mean the brake pedal position sensor on the vacuum booster? If it's this you're talking about they fail very often.

Guntar13 · Post by **Guntar13** » 13 Oct 2017, 07:39

Yeah yeah sorry meant vacuum booster, I’m not so much worried about that one but the other codes are the ones that are getting to me. Thanks for the reply!

Post by **precopster** » 15 Oct 2017, 03:52

P0447 can be a bad evaporative vent valve which is located on the fan shroud. It has a 2 pin connector and 2 x 6mm ID hoses connected. Check the connector by reconnecting multiple times to scrape off corrosion or dirt. Also make sure the pins are clean. Can also be a bad rear O2 sensor or a bad cat converter.

Post by **RickHaleParker** » 15 Oct 2017, 06:21

P0447 and P2400 are both open circuit codes in the Evaporative Emission Control System. The first thing I would look for is loose or corroded connections.

Guntar13 · Post by **Guntar13** » 15 Oct 2017, 07:33

Are you referring to this valve cause it has three hoses or there is another farther down attached to the shrowd but has no electrical connector just hoses... also how likely that something has come loose at the charcoal canister in the rear? It seems pretty well protected

Mr. Ray · Post by **Mr. Ray** » 31 Oct 2017, 19:11

I just replaced my brake booster pedal sensor on my 2004 s80. Now I have a hard brake pedal and a rough idle. Does anyone know what this could be. Thanks for any advice.

zjevik · Post by **zjevik** » 31 Oct 2017, 23:04

That sounds like an air leak. When I changed my brake booster I didn't change the brake booster pedal sensor and reused the old one. Soon after that I found out I still have an air leak and finally found out that the seal around the brake booster pedal sensor hardened.
See, if this is not your case by pulling or moving the pedal sensor when the engine is running.

Mr. Ray · Post by **Mr. Ray** » 01 Nov 2017, 14:03

Yes that was it. I had some incense and lit one and put it next to the pedal sensor and it immediately began to pull the smoke into the booster. I truly appreciate your help. Thanks