Click Below to Visit Our Sponsors

• O1M Technicians Diagnostic Guide mentioned in January Transmission Digest

• Newly Updated 41TE/42LE Codebook now available for download. Click Here.

• NeverBind, our latest "Kewl Tewl"

• Questions about new ATSG Pricing Plans and Online services orTransonline?

• SAFETY ALERT, Ford Fire Suppression Systems

• NEW VERSION of CD-ROM SOFTWARE NOW AVAILABLE-Order Now!

• NEW WEST COAST HOURS

• Latest Corrections and References for Seminar and ATSG books

I Don’t Like the Cold
By
Wayne Colonna

The past winter months brought to surface a no up shift out of first gear when cold with the SAAB/Volvo 50-
42LE transmission. When it warms up all shift sequences are restored. The time varies in which this occurs.
The problem has been traced to a mechanical failure of the number 1 shift solenoid with the black connector as
seen in figure 1. Both the number 1 and number 2 shift solenoids are normally closed solenoids when off and
opens to exhaust when energized. Figure 2 provides a first gear hydraulic. Shift solenoid 1 is off and shift
solenoid 2 is on.With shift solenoid 1 off, pressure is allowed to stroke the 1-2 shift valve. When the 1-2 shift
needs to occur, this solenoid is energized. The pressure from the solenoid stroking the 1-2 shift valve is
exhausted and the valve closes by spring force. Line is then directed into the B2 circuit as seen in figure 3. And
as previously stated, in cold climate conditions, this solenoid does not open to exhaust when energized

More>>
PDF or Web page