Codes P0133 and P0446

marcus · Post by **marcus** » 23 Jan 2018, 04:39

Hello,

I have Volvo s60 2002 , 2.4 170hp. 370 k miles.

I am reciving those two codes. Do they mean something in particular when they show up togheter? Is this any helpfull indication how to solve the problem?

Anyway, what should I check to solve this issue?

Post by **abscate** » 23 Jan 2018, 05:32

Your P04xx code is telling you your evap system has leaks or failed parts. Once you allow air into the system' the OXS will fault in one of many ways.

Get a smoke test to find your evap problems first, then clear codes and see if the OXS codes come back

Post by **RickHaleParker** » 23 Jan 2018, 08:31

P04XX is Auxiliary Emission Controls

P0443 - P0445 is the Evaporative emission system (EVAP) valve.
P0446 - P0448 is the Leak diagnostic unit.

P0446 is Leak diagnostic unit, valve, Signal too high.

Possible source

Short-circuit to supply voltage in the signal cable
Defective Leak diagnostic unit.

: LeakDianosticUnitgif.gif (9.8 KiB) Viewed 1423 times

marcus · Post by **marcus** » 23 Jan 2018, 08:43

For codes I have just bluetooth box which I connect to OBDII and read them on my celphone with special app.

P00446 - has description -"Evaporate Emission Control System Vent Control Circuit". Is the description directly driven from my volvo computer or this is random description for the code. Because as I am oriented they are universal across automotive.

Post by **RickHaleParker** » 23 Jan 2018, 09:22

The description is the software's (On your phone) interpretation of the codes in the car's OBD.
P0446 is vaguely universal. Your software is give the vague universal interpretation.

What I listed above is the specific interpretation for a 2002 Volvo S60.

marcus · Post by **marcus** » 24 Jan 2018, 02:27

Can be the CODE P0446 caused by damaged gasket on fuel cap?

Post by **abscate** » 24 Jan 2018, 05:26

Unlikely , you are more likely to get P0455.

Find a friend with a Volvo and swap caps for a week after you clear codes.

marcus · Post by **marcus** » 24 Jan 2018, 06:06

How to investigate and eliminate - "Short-circuit to supply voltage in the signal cable"?

Post by **abscate** » 24 Jan 2018, 10:39

With a wiring diagram, look at the supply plug voltage on the emission pump - see if it is 12 volts at the right time. You can also supply fused 12VDC to the pump and see if it runs - if it doesn't that is the likely cause of the error code.

Post by **RickHaleParker** » 24 Jan 2018, 11:09

How to investigate and eliminate - "Short-circuit to supply voltage in the signal cable"?

Pull the connector to the Leak diagnostic unit. Turn key to POS II (on) measure voltage to ground on all pins of the Leak diagnostic unit harness, only one line should be supply voltage. If more then one is supply voltage you have a Short-circuit to supply voltage in the signal cable.

Eliminating a Short-circuit to supply voltage is a matter of tracing the shorted signal wire until you find the short. Else, you can replace the harness with a known good one.

A damaged fuel cap gasket would not produce a P0446. Most likely produce a P0440 (Leakage).