M4.3 to M 4.4: Really that simple?

Post by **Chuck W** » 06 Jun 2022, 18:23

It looks more like it's the accelerometer that is causing the code. It's referring to the one attached to the front subframe.

Check it's connector or swap it out with another.

Post by **scot850** » 06 Jun 2022, 19:02

If I recall correctly the barometric pressure sensor, the accelerometer and the A/C high pressure sensor are all on the same circuit.
It has been a while but I think I am correct on this.

Neil.

Geevs · Post by **Geevs** » 06 Jun 2022, 21:46

Thanks for the replies.

I recall reading that the accelerometers in the 94-97 850s are under the cowl between the cabin filter and the passenger wiper motor. I haven't checked yet. If the accelerometer is indeed under the cowl, is this functionally any different from the one in the 98 x70s mounted in the front subframe?

Post by **Chuck W** » 07 Jun 2022, 06:24

On our 97's the accelerometer is on the front of the subframe. It'll take you 2 seconds to stick your head under the front of the car to verify if it's there or not.

Geevs · Post by **Geevs** » 16 Jun 2022, 09:21

Which sensors are in the 1998 s70/V70 that M4.4 expects to find but are not in the 850s? I recall they are:
- accelerometer
- barometric sensor
- MAP
- IAT

Anything else? Where are the location of these sensors in the x70? I'm heading to the junkyard this weekend to look for these.

Thanks!

Post by **Chuck W** » 16 Jun 2022, 10:06

Is your accelerometer missing?

Not sure why you need to add any of that stuff, however. The car should already have an accelerometer and a baro sensor. The IAT is not needed.

When I did the initial M4.4 conversion on my '97 T5, I set the injector calibrations, disabled the rear O2 stuff, disabled the IAT, did the AC software mod and that was it. Didn't add anything.

The MAP sensor is not a stock item, it is an add-on for data-logging to get boost, as the stock programming does not use such a thing.

Geevs · Post by **Geevs** » 26 Jun 2022, 16:21

I looked at the 2 possible location for the accelerometer as per the diagram below:

http://volvospeed.com/vs_forum/topic/17 ... nt=2424806

and still didn't not find it. My car is a Canadian 96 850R with factory M59 5-speed. These were special orders for the Canadian market that was not sold in USA. The ECU is M4.3 but is not OBD2 compliant as it doesn't have a rear O2 sensor.

Anyway, the accelerometer is definitely not under the wiper cowl. I searched near the front subframe under the AC compressor and didn't see anything mounted on the subframe nor did I see any unused wiring connector.

I did find a sensor in front of the bottom of the radiator facing the opening of the R bumper front lip. It is connected to a wiring harness. What is this sensor - the barometric pressure sensor?

Is the acceleometer needed in M4.4 and can it be disabled?

Post by **Chuck W** » 26 Jun 2022, 18:50

Pictures would help.

Sounds like the outside/ambient air temp sensor for the ECC.

Geevs · Post by **Geevs** » 27 Jun 2022, 10:06

I went back into Tuner Pro and disabled the Accelerometer in both locations. Reflashed and all good now.