1996 Volvo 850 Not shifting into low when I stop the car

Tiny
JEFFREY SHERMAN
  • MEMBER
  • 1996 VOLVO 850
Transmission problem
1996 Volvo 850 Front Wheel Drive Automatic 160, 00 miles

Approx. Six months ago I had the PNP switch replaced because (i) the car would always start out in high gear and (ii) an orange-colored arrow on the dashboard was always blinking. Based upon my internet reseach, I had concluded that the PNP switch was bad; the dealer confirmed my conclusion; so, I had the PNP switch replaced.

Last week the car, when hot (but not when cold), began not down-shifting infrequently when I came to a stop. The problem is most infrequent; there is no flashing arrow displayed; and if I quickly, momentariily and forcefully depress the gas pedal for a second or so, the car will most of the time immediately downshift into low gear, and all is fine (prioir to replacing the PNP swith months ago, this "tactic" did not result in the car's down-shifting).

I do note that the trans. Fluid, when hot, does go a little above the "FULL" mark on the trans. Dip stick. I had the fluid replaced approx. Four months ago, but this infrequent problem (car will not always downshift when the car is hot) just began last week.

Help, please.

Thank you.
Tuesday, March 9th, 2010 AT 9:38 PM

5 Replies

Tiny
DOCFIXIT
  • MECHANIC
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Hi
Transaxle shifting is controled by solenoids that respond to TCM signals. System is self diagnostic so need to have TCM hooked up to scan tool and see what fault is ocuring. Will trans manualy down shift if shifter moved to First gear?
Hope this helps
Thanks for donate
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Wednesday, March 10th, 2010 AT 9:19 AM
Tiny
JEFFREY SHERMAN
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Your answer to my first Q (my reply to your answer is below):

Posted at Wed Mar 10, 2010 7:19 am
By Docfixit, Certified 2CarPros Master Technician
Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8Reputation: 4773.8 (4774) Give Feedback | Votes: 79

Hi
Transaxle shifting is controled by solenoids that respond to TCM signals. System is self diagnostic so need to have TCM hooked up to scan tool and see what fault is ocuring. Will trans manualy down shift if shifter moved to First gear?
Hope this helps
Thanks for donate

__________________
1. Thank your for the super faxt response and for the advice re TCM signals.

2. The next time the car won't downshift, I'll manually shift into first gear, see what happens, and let you know.
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Wednesday, March 10th, 2010 AT 9:28 AM
Tiny
DOCFIXIT
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Possible speed sensor fault or First shift solenoid if it manually shifts that may provide a clue.
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Wednesday, March 10th, 2010 AT 9:43 AM
Tiny
JEFFREY SHERMAN
  • MEMBER
  • 3 POSTS
In my earlier e-mail to you today (Wed.) "Super faxt" should be "super fast."

I'll let you know about (i) downshifting and (ii) the result of my visit in the near future to the Volvo dealer.

Too bad for me you are not in or near Columbus, Ohio.

Respectfully,

JPS
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Wednesday, March 10th, 2010 AT 9:49 AM
Tiny
2 LINSEY
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Thank you for using 2CarPros. Com. We appreciate your donation and look forward to helping you in the future.
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Friday, March 12th, 2010 AT 1:58 PM

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