I have S70 98 and the engine check comes on. the code is P1307.
I went to the dealer, paid $100 and they diagnosed the problem as bad Acelrometer sensor part number 6842539.
I ordered the part, it is Bos part 0273101021, replaced it, and it did not help.
I reseted the Code, but after runinig ther engin for a few minutes, the same code.
Can you help please?

When your scanner pulls the code what info does it give?
What sensor does it say is bad?

The scanner states "Manufacturer Controlled Igniition System or Misfire".
I am using Actron CP9135

The reason I aksed is because if I am not mistaken that sensor is tied in with the A/C high pressure switch.
Are you having a problem with your A/C?

The compresor is cicling on and off. When I add 134a, the pressure started to build up and the release valve on the compressor activated, and released the gass. I aded dye, and it spraied from the release valve on the radiator fan, up to the other side of the car.

The high pressure switch is probably bad!!
It should have kicked the compressor off.

How is the A/C connecting to that Error message? I am running the car without activating the A/C. In the Volvo book by Chilton there is did not see any connection between the Accelerometer and the A/C. The Accelerometer sensor is a MAP sensor and is to differentiate the road vibration from the engine vibration.

Yes but the power supply is shared by the high pressure switch.
Or the ground I forget which one.

I have run into this before and it kicked my butt.
I got paid like 1/2 hour for 4 hours work to figure out it was the high pressure switch.

Thanks.
I will replace that unit. I will check up with you after I will replace it.

To test out the idea that the high pressure sensor is the problem, can I disconnect it before replacing it?

You can try but I don't remember if the code will stay cleared.
Does you scanner tell you if the fault is permanant or intermittant?

No, the scanner does not give me this informatin. I know that it is temporary. I cleae the code, drive the car and the check engine comes on later.
can you direct me to the high presure sensor please.

Follow the A/C pipes from the low pressure switch towards the front of the car.The sensor is located in the front of the pipe like next to washer fluid fill.the pipes sit down on the body like on the frame rail.

Can you help me to locate the fule tank pressure sensore?

I need the location of the Atmospheric pressure sensore too.
The Accelerometer power lead is connected inside the ECM to the tank pressure sensore, atmospheric pressure sensore, and the A/C pressure sensore.
They changed the Accelerometer location in my car. Insted of iside the fire wall, it is on the care front between the radiator and the engin.

Fold down both rear seats then remove the carpet from the trunk.
Then remove the metal covers that have the 10mm nuts.
On some of the cars you can get to it without removing the tank and some you have to drop the tank.
It should be a black sensor with a hose and a plug going to it.
Once you remove the covers then you can look in the holes and try to find it.
It is most likely more towards the driver side.

Yes, I found it, thank you. I took the ECM (computer) out of its socket. I disconnected the sensors, and checked for continuity from the sensors to the ECM socket, and it is all good.
No short wires.
I checked on the ECM and found that between B29 and B28 (a/c pressure sensor connector line 1 and 3) there are 840 ohms.
I checked the sensor and found that on the a/c sensor between leg No 1 and 3 there are 8 ohms. Between pin 1 and 2 and pin 2 and 3 there are 12K ohms.
Do you know if the measurements are good or it is indicated on bad parts (ECM or A/C pressure sensor?)

Sorry I don't have the specs for the measurements anymore.

I replaced the Pressure Sensor, after a short drive, check engine light came on. I found that if the car is hot, the code P1307 is permanent.
Last winter, my battery died, I tried to charge it, but it did not work. I jump started the car, and I think that the engine check came up after that.
I also get P0440 (EVAP) bur very intermittent.
Do you have any suggestions?

Which sensor did you replace the tank sensor or the A/C high pressure switch?

I replaced the A/C high pressure switch.

I also beleive the fuel tank pressure sensor is on the same circuit as well.

Hi there.
You where right the first time. The A/C pressure sensor was bad.
I checked for the bad code, and then I replaced the sensor, and checked again, in a short period of time (10 minutes).
And it is wrong. The bad A/C sensor caused the ECM (computer) to get hot, and I needed to let it cool down of for an hour before checking it again. The resistance between terminal #1 and 3# on the bad sensor was 8 ohms, and on the good sensor the resistant is very high.
Thank you for your help. You are a real Pro.

Simon

No problem anytime.

Im glad I could help.