intermittent limp home

mapdoc · Post by **mapdoc** » 22 May 2016, 09:23

My '97 850 T-5 started going into limp home intermittently for several weeks ago. I initially pulled a P1618 code, I reset and the code is gone but car is still reverting to limp home mode. I had the same problem last summer and replaced the B-cable connector and the problem went away.

The transmission usually works fine after I let the car sit overnight or a day or two. However, when I try to restart the car after it worked fine, the car goes into limp home mode. I rowed the shifter back and forth which didn't help.

In the past year I have replaced the cam shaft senor, the PVC system, the struts, rear brakes, T-belt, water pump, etc. I think the problem is electrical, but I don't know where to start.

Any help you be appreciated>

Sommerfeldt · Post by **Sommerfeldt** » 22 May 2016, 12:36

How exactly did you reset that code? It's not a very easy code to reset, usually.

A wild stab in the dark is a bad solenoid, but it could be any number of things. You need to get a specific diagnosis on your transmission done.

- S

mapdoc · Post by **mapdoc** » 22 May 2016, 14:46

Thank you for the reply. I reset the P1618 code using an Innova 3100 reader. I tried to take the car to Cottman, but was told they can't read the codes from a 1997 car.

The car has been sitting for about 6 hrs and it just started and drove fine. I turned it off and it immediately went back into limp home mode -

Sommerfeldt · Post by **Sommerfeldt** » 22 May 2016, 15:03

And you have the flashing arrow, indicating a transmission fault, right?

A P1618 isn't very specific, so you need further diagnosis. If you can't get the tranny's brain to tell you anything else, I guess take it over to Bergeron Volvo (with fingers crossed that it's not the AFV guy) or some other Volvo dealer, and have them run diagnosis. The intermittent nature of the problem doesn't really give much away either - it could be pressure related, temperature related, could even be a bad connection somewhere. The code seems to indicate that, but it can't really be trusted.

- S

mapdoc · Post by **mapdoc** » 22 May 2016, 18:17

There is no flashing arrow. The first indication that the car is in limp home mode is when I start it there is no orange arrow. When the car sits, I have the orange arrow and the transmission is fine.

All four of my Volvo's (240, 850, S70, XC60) have come from Bergeron. They are a good dealership, but, as with all dealerships, any type of repair is very, very, very expensive (which I am trying to avoid).

Post by **scot850** » 22 May 2016, 22:46

Sommerfeldt makes a good point in that sometimes you have to go where you can at least get answers. This does not mean having the dealer do the repairs, but at least get them to diagnose the issue with the proper test equipment. It is cheaper than speculating and throwing parts at the car not knowing what is actually broken.

Neil.

Sommerfeldt · Post by **Sommerfeldt** » 23 May 2016, 02:28

Exactly what Neil said - have them do diagnosis, then limp it back home and decide what to do with the new information.

One thing I don't get - you say you've got the arrow when the car sits - you mean while you're idling? And then it goes away when you start to drive it? If the transmission is fine, you should not have a lit arrow when you're in Drive. You should have an arrow when:

- In Winter mode. (constantly lit)
- In any other position than D or R (constantly lit)
- When there's a DTC set in the tranny (flashing)

When you start the car, you should see the arrow for a moment when the key passes II, along with all the other "idiot lights". So, which scenario fits yours?

- S

mapdoc · Post by **mapdoc** » 23 May 2016, 08:17

When the car sits -- I "...see the arrow for a moment when the key passes II, along with all the other "idiot lights"" and the car runs/drives fine. When I then turn off the car and try to restart - I do not see arrow at any time and the car is in the limp home mode.

1) Will I damage the car driving it to the dealer (~25 miles) highway/ stop-go traffic when it is stuck in limp home mode?

2) Will the dealer be able to read the transmission codes even if I erased them with the Innova 3100?

Thanks for the help

Sommerfeldt · Post by **Sommerfeldt** » 23 May 2016, 10:27

I'm a little bit confused. Which some say is my normal state, I guess...

But, seeing the arrow right as you turn the car on, along with the other warning lights, is normal behavior. The way I understand you, you don't have either a flashing nor a steady arrow while the car is actually running and/or being driven - is that right?

If so, I'm wondering how you've arrived at the conclusion that you're in limp mode? This condition - it'd probably help if you describe exactly what's happening to make you think it's in LHM - only presents itself after a warm start, and you have no codes set after you nixed the one you had?

As for your questions, 1) no, it shouldn't. LHM is made to put the tranny in a mode where it only operates within very gentle conditions. 2) Maybe. But if you're really in LHM, then there will be other codes set. If there aren't any, then further investigation is definitely needed.

- S

mapdoc · Post by **mapdoc** » 23 May 2016, 15:32

Sorry for the confusion. When I start the car in the morning (or after it has sat for a while) I have yellow arrow as I am turning the ignition and the car works perfect. If I then turn the car off and restart, there is no yellow arrow while turning the ignition (and I can't get it into winter mode) and the car seems like it is stuck in 3rd gear. It will move, but very slowly and it will jerk when I put it into reverse. Is this not "limp home" mode?

Thank you for your help -