January 01, 2013

55-50/51SN Common Problems After Remanufactured Valve Body Installation

Solenoid Wire Color Chart

SolenoidConnector ColorWire Color
SLUBlack1 Green, 1 Brown
SLTBlue1 Green, 1 Gray
SLSGreen1 Blue, 1 Red
S2Black or GrayBlack
S4Blue or GreenPurple or Red
S5Green, Red or GrayBlue or Black
  1. Shift Quality & Engagement Feel Concerns: This is a computer controlled transaxle that uses adaptive learn to adjust the shift feel and engagement timing. Whenever the transaxle is rebuilt, replaced, or if the valve body is replaced, the shift adapts must be cleared and relearned. The procedure is different for each manufacturer. Numerous engagement and shifting problems can remain after rebuild that the relearn procedure will correct. Most vehicles need computer software reflashes to correct specific shift & engagements problems.
  2. No 3rd Gear: Do NOT remove the big bolt on top of the transaxle - it is NOT for filling the transaxle; it is the band anchor bolt. Removing the band anchor bolt causes the band to fall out of position, resulting in no 3rd gear.
  3. Wrong Gear Starts/Delayed Engagements: It's not uncommon for solenoid wires to be installed on the wrong solenoids, especially the S1 switched with the S3. Do NOT go by the connector color, use the wire color chart.
  4. Assorted Solenoid Codes: Assorted solenoid codes occur when wires are pushed out of the harness side of the transmission connector on Volvos.
  5. Electrical Codes for the SLU, SLS & SLT Solenoids: These occur when spade connectors bend out of the way and create an open circuit or intermittent connection. Spade connectors are very thin and easily bent. Please use extra care when pushing wire connectors into place.
  6. Slips, Delays & Low Line Pressure: Please use care when installing the valve body so that the valve body to case gasket does not fold over and allow air into the suction side of the pump, creating low line pressure, slips and delays.
  7. 2-3 Flare: Most vehicles have a software reflash for this complaint. During transmission overhaul, shorten the servo travel to .1 00"-.125". Volvo also has an upgraded servo - see Volvo Bulletin # 43-37 dated 2-25-03. Air check the servo through the case to verify no leakage at the O-rings on the ends of the tubes.

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