Volvo 850 tranny problem

Gdelamare92 · Post by **Gdelamare92** » 09 Nov 2019, 16:09

Ok... so I bought a 1997 volvo 850 GLT 2.5 auto. Without jetronic or motronic. As a non runner(fuel pump and relay had gone)... anyway. Over a year later and many vacuum hoses replaced I now have an issue that just popped up. If I start the car and shift straight to drive it's fine. But if I have to shift into winter, 3 or L then back to D, it gets stuck in what feels like 4th(last gear) and unless I turn the car off and back on again it remains like that. Same thing happens if I select reverse and drive in reverse. All this with the flashing orange arrow on the dash. I went through a deep puddle earlier. I'm thinking maybe the tranny ECU got wet or the plugs got wet...

Any advice welcome

TIA

Post by **jreed** » 10 Nov 2019, 07:20

The behavior you describe is similar to what happens when the PNP switch in the transmission control circuit fails or gets gummed up. You can sometimes clear this problem by rapidly moving the transmission selector back and forth several times to try to clear up the contacts in the switch. If you search for "PNP Switch" here, you'll find a wealth of information about the problem and methods for resolving it.

Gdelamare92 · Post by **Gdelamare92** » 10 Nov 2019, 07:32

jreed wrote: ↑10 Nov 2019, 07:20 The behavior you describe is similar to what happens when the PNP switch in the transmission control circuit fails or gets gummed up. You can sometimes clear this problem by rapidly moving the transmission selector back and forth several times to try to clear up the contacts in the switch. If you search for "PNP Switch" here, you'll find a wealth of information about the problem and methods for resolving it.

Weirdly enough. Started it up this morning... it's fine now. Read the codes. None stored. Must have been a glitch in the matrix.

Post by **Clemens** » 11 Nov 2019, 16:21

Gdelamare92 wrote: ↑10 Nov 2019, 07:32 Must have been a glitch in the matrix.

More likely water or dirt getting up to the pnp swirch shorting it our or sthg. Good luck it stays away. If the problwm returns, the PNP is a suspect.