Hello,
I just got back from a little hunting trip. Couldn't make it up an icy hill and while my tires were spinning my transmission arrow started flashing. I read the code and got 3-1-1, RPM signal from transmission missing. What does this mean? Thanks

 

311/P0715 ....Check engine light on - Yes .. RPM Signal Missing Or Transmission Speed Sensor Signal Missing.

DTC 311/P0715: RPM SIGNAL MISSING
1) Ensure ignition is off. Connect measuring unit to TCM.
Measure resistance between measuring unit terminals No. 1 and 2. If
resistance is 300-600 ohms, sensor and wiring are okay. If resistance
is not 300-600 ohms, go to next step.
2) Measure resistance between transmission 26-pin connector
terminals No. 16 (Yellow/White wire) and No. 17 (Yellow/Brown wire).
If resistance is 300-600 ohms, sensor is okay. Check wiring. If
resistance is not 300-600 ohms, check wiring. If wiring is okay,
replace sensor.

If you need to replace it, 10mm hex head screw and it can be done easily without taking much apart.

 

thanks! when it says connect measuring unit to TCM, does this mean to the box or the pins underneath? I've never removed either module and have little experience with wiring/electrical systems

 

Have you downloaded the service manual for the car yet ??

 

no, where can i get that?

 

Download the service manual and then open it up and check out auto trans diagnosis.

https://volvoforums.com/forum/volvo-...ownload-58576/

 

thanks Kiss, you have all the resources! ill post tomorrow hopefully with some results

 

i don't have the measuring unit so idk how i can measure the ohms for step one

 

On page 24 it shows the numbers of the pins on the connector so you can use that to find the correct pin on the TCM.
I haven't done this test or had the TCM out of it's "home" on my car. I am assuming the measuring unit is just a DVOM (Digital Volt Ohm Meter) as they are referring to reading the resistance (Ohms).
It wouldn't need to be a digital meter, just that most people have digital meters these days.

I would disconnect the battery just to make sure if you do hit the wrong pins you don't blow the fuse in the meter from hitting a 12volt source.

When you said you didn't have the "measuring unit" were you thinking it was a dedicated testing tool ??

You might want to see if anyone agrees or disagrees with me before you proceed to pull the TCM to test.

 

i understand the pin connection but i thought i needed the measuring unit to read the tcm and then using a voltmeter to read the pins where it connects into. i tried reading those pins anyways but couldn't get a reading with my voltmeter