Limp Mode/ Flashing Up Arrow

bubbeck · Post by **bubbeck** » 26 Oct 2020, 10:29

Hey folks,

I was driving to work the other day and got the classic limp Mode/ Flashing Transmission Up arrow. Went to the shop and got the codes pulled, and had an AT-222 (shift solenoid S2), AT-143 (kickdown switch signal), and a code for the PNP switch (forgot the number). Cleared the codes and got about another 50 miles of driving in before it went into limp mode again. This time I just had AT-222 and AT-143, no PNP switch code.

I know most people typically jump to replacing the PNP switch for this kind of thing, but before I throw parts at this how can I rule out shift solenoid 2? To be honest, the solenoid seems more likely since that code came back first, but I'm really not jazzed about doing that job. When I got the flashing arrow, I turned the car off and did the shifter-row, which didn't clear the flashing light but allowed it to shift into gears 1-2. However, when I got the code the second time, just turning the car on and off allowed it to shift normally as well (no flashing light) so I'm not convinced the shifter row did anything the first time.

For those of you that have done the solenoid s2 job, does the transmission still last a while after replacing the solenoid, or is just a sign of worse things in the future? As much as I love the 'ol wagon, I'm starting to get to the end of my rope with the car, after just fixing a bunch of stuff, and still needing to drop $1000 on a new muffler and windshield just to get it MA legal....

Side note, anybody want a project 1998 V70XC?

bubbeck · Post by **bubbeck** » 26 Oct 2020, 11:11

Also, could this have been caused by overfilling the transmission fluid? I had checked the fluid not long before this started happening, thought it was low and added a half quart or so...

Post by **abscate** » 26 Oct 2020, 11:36

Can be caused by overfill. Did you use the procedure for checking fluid (good) or just check the disstick with the car off (bad)?

bubbeck · Post by **bubbeck** » 26 Oct 2020, 15:11

Yep, I used the procedure to check the fluid (drive around 1/2 hr, shift through all the gears for 5s, wait 3 min). There is some fluid above the high line, but it'd hard to know what's the fluid level and what is ATF from the dipstick tube. The hot lines don't have a super distinct amount of atf on them, which is why I thought it was low in the first place. I suppose a quick drain/fill couldn't hurt?

Post by **RickHaleParker** » 26 Oct 2020, 15:36

AT-222 Clean the connector to the TCM and check wiring for shorts and opens. Sometimes just resetting the TCM in it's socket will fix this but may as well clean the connector and check it out while you got the TCM out.

bubbeck · Post by **bubbeck** » 27 Oct 2020, 09:11

Thanks, that sounds like a good and easy thing to check... Do you happen to know what pins on the TCM go to the solenoid S2 (or have a TCM connector diagram)? Is there another connector on the transmission side I should also check?

Post by **RickHaleParker** » 27 Oct 2020, 18:07

bubbeck wrote: ↑27 Oct 2020, 09:11 Thanks, that sounds like a good and easy thing to check... Do you happen to know what pins on the TCM go to the solenoid S2 (or have a TCM connector diagram)? Is there another connector on the transmission side I should also check?

A26 on the TCM connector. Pin 22 on the transmission connector.

Most of the time pin numbers are molded into the connector. Look next to the pins. You might need good lighting and a Loupe to see them

Post by **abscate** » 28 Oct 2020, 01:02

I’ve got both a windshield and a 1998 at heading for scrap in Albany soon, if you are interested. Can deliver too.

Available on the Socialist Sliding Scale of $0 to Fair market Value

I’ve never removed a Volvo windshield though, might not be too Easy

Post by **wizechatmgr** » 28 Oct 2020, 07:03

abscate wrote: ↑28 Oct 2020, 01:02 I’ve got both a windshield and a 1998 at heading for scrap in Albany soon, if you are interested. Can deliver too.

Available on the Socialist Sliding Scale of $0 to Fair market Value

I’ve never removed a Volvo windshield though, might not be too Easy

E-string or piano wire, cut around the seal typically.

bubbeck · Post by **bubbeck** » 14 Nov 2020, 13:25

Hmm, well I did a transmission fluid drain/ fill and cleaned and checked the TCM connector. My connector doesn't seem to match your wiring diagram RickHaleParker - it seems to match the diagram http://www.volvotips.com/index.php/850- ... g-diagram/. I checked the pins with a multimeter, and found 13.5 ohms between 27-29 (S1 - ground) and 14 ohms between 28-29 (S2 - ground). Unfortunately, got limp mode again within about half an hour of city driving, so cleaning the connector/reseating the TCM wasn't the quick and easy fix. What would you all check next? PNP switch, or dive into replacing solenoid S2?