98 V70 Famous P1308 Code

grunv70 · Post by **grunv70** » 15 Feb 2015, 11:11

Hey guys, hopefully someone can shed some light on this. I searched everything I could, but still have the pesky problem.
Car is 1998 V70 2.4 Code is 1308 which is usually the accelerometer module on the front subframe. From what I understand, those are rare to fail, although they do sometimes. The part being expensive, I got a few used ones from a junk yard. 5, to be exact. Don't know if its just me, but I doubt I found 5 bad sensors.
Anyone had this problem? Actually get it resolved? Its frustrating since it runs very well, and I need to smog it to register it (car was given to me dead, and has been resurrected).
I understand this can be an AC issue sometimes as well, but I am a little lost as to what exactly. Theres only 3 sensors/switches on the AC lines, low pressure line by the firewall, thermal on the compressor itself, and one by the condenser.

Help??

draser · Post by **draser** » 15 Feb 2015, 13:15

If your sensor has 3 pins, center pin should have 5v on it, and pin 1 is ground. Can you get a multimeter and check voltage to pin 2 (center) between pin and some clean point on chassis, connector unplugged and key on 2? Then remove key, switch meter to ohms and check ground from pin 1 to chassis.

grunv70 · Post by **grunv70** » 15 Feb 2015, 14:25

Pretty sure I did most of that. I get 4.9V, I'll check ohms right now

grunv70 · Post by **grunv70** » 15 Feb 2015, 14:39

*Correction
My pins are in a different order.. Pin one is the 5V power, center is ground, and #3 is nominal voltage line.. I get 4.9V between pin one and two, but no reading between pin one and vehicle ground.
Cant seem to get a ohms reading from ground pin to ground with the key off..

Post by **Ozark Lee** » 15 Feb 2015, 15:00

That code is almost always the wiring or the connector.

...Lee

draser · Post by **draser** » 15 Feb 2015, 15:04

Key has no effect on the ground wire. I'd check all three to ground, key off. Just in case pin-out is different.

grunv70 · Post by **grunv70** » 16 Feb 2015, 15:07

I do have 5V. The odd thing I've found is that I have 5V between ground terminal and reference terminal. If I try reference terminal and vehicle ground, I can't get a reading.
And ground terminal to vehicle ground - tried to check continuity and ohms but no reading either.

Just swapped a couple of AC sensors, both high and low. Still same.

The harness doesn't seem to be long, and the ECU is right there, but am not sure what the next test could be and if the ground can be bypassed to test...

draser · Post by **draser** » 18 Feb 2015, 11:47

You have the 5v between 1-2 which is good. You should have about 2.5v between 3 and ECU ground for a good sensor. It seems chassis and ECU grounds are isolated.

Lurch · Post by **Lurch** » 03 Mar 2015, 08:19

I'm also chasing P1308, and have also replaced the accelerometer from a junkyard (only twice). I found this quote somewhere a couple of months ago and it seemed important enough to write it down:
"The accelerometer power cable is connected inside the ECM to the fuel tank pressure sensor, atmospheric pressure sensor and A/C pressure sensor power cables. If anything happens to any of these cables, all four will be affected. A/C pressure sensor wiring is pre-routed, even on cars without A/C, and should always be checked."
So, I've started checking the voltage to those sensors. Accelerometer has 4.9V supply, 3.69V signal. Fuel tank pressure sensor has 1.3V supply, 1.2V signal, A/C high pressure sensor seems to have 1.25V supply and 1V signal, and I don't have an atmospheric pressure sensor. Something's out of whack--a bad ground, bad sensor--but I'm just not sure what to do next.