Transmission Gremlins

Knoxvegas S70 · Post by **Knoxvegas S70** » 16 Feb 2010, 21:25

Ok so for the past year I have been driving around with the flashing arrow and check engine light. From what I remember the code was a 5xx but I do remember it said vehicle speed sensor. I finally got a hold of a VSS and put it in today. Disconnected the battery and before turning on the car, I flipped the key from off to the on position several times and moved the shifter up and down several times. Well I no longer have the flashing arrow or a CEL but the transmission wont shift from 1st gear until I press the winter button which shifts it to 3rd. Eventhough there is no CEL my code reader picks up a P0909 and p0F0F

Also if I let off the gas in 1st gear it acts like I put it in neutral and the revs go down. If I step on the gas it
just revs until it gets to the right point and then starts to accelerate.

With the old VSS the transmission shifted perfectly. What do you guys think.

Post by **Ozark Lee** » 16 Feb 2010, 21:59

You have a lot of parts in motion at the moment. The VSS on your car should be a signal from the ABS module - I may be wrong on that but luckily I have other people that have my back and they will correct me if I am wrong. On the '96 and on 850s that is definitely the case but once you get to the V/S series things change.

Is your ABS and or TRACS light on?

If so that is where I would start.

All of the '96 and on modules will fail, it is just a matter of when. The good news is that they are very good about fessing up about their failure and turning on a warning light on the dash.

...Lee

Knoxvegas S70 · Post by **Knoxvegas S70** » 16 Feb 2010, 22:14

I had the abs module repaired when the lights came on a few years ago. The speedo still works and I get no cel or flashing arrow with the new sensor. But It wont shift from 1st gear unless I press the W mode and then it switches to 2nd or 3rd. Its not in limp mode either because it starts off fine.

I ended up putting the old sensor back in and it shifts normally but the I get a cel and flashing arrow. The lights drive me nuts otherwise I would leave it alone.

Any idea what a p0909 is?

Post by **Ozark Lee** » 17 Feb 2010, 13:59

P0909 is a transmission gate selector control error. It sounds like the linkage is messed up.

...Lee

Knoxvegas S70 · Post by **Knoxvegas S70** » 06 Mar 2010, 12:37

I have been trying to fix my problem for while now and still cant figure it out. I ended up taking the pnp switch apart to clean it and regrease it. I was hoping that would somehow fix the problem but still no luck. Ive read on volvospeed that when people do manual swaps they have to tap into the wheel speed sensors. I have an automatic and thinking about doing this on my car but unsure exactly what wires to tap in to.