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so after the last month I have changed the plugs, wire, rotor, shocks, idler arm and bracket, rear pinion seal, pumpkin gasket and oil, radiator, battery, drum shoes, and added a trailer brake controller. finally ready to do some serious driving and I get a P1870 code while pulling the pop up to the campground. we made it there but i need this thing in running shape for taking the camper to sturgis in 2 weeks please help. I just order this product off amazon a TCC valve upgrade replacement by Fitzall and also going to test the TCC PWM soleniod anything else i can do? 

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DTC P1870 sets if the following conditions are met for three TCC cycles with reported excessive TCC slip conditions, two consecutive times.


  • No TP DTCs P0122 or P0123
  • No VSS Assy. DTC P0502
  • No TFT Sensor DTCs P0712 or P0713
  • No TCC Sol. Valve DTC P0740
  • No 1-2 SS Valve DTCs P0751 or P0753
  • No 2-3 SS Valve DTCs P0756 or P0758
  • No TFP Val. Position Sw. DTC P1810
  • No TCC PWM Sol. Valve DTC P1860
  • The engine speed is greater than 450 RPM for 8 seconds.
  • Not in fuel cutoff.
  • The engine torque is 50-450 lb ft.
  • The gear range is D4.
  • Not in 1st gear.
  • The TP angle is 9-35%.
  • The TFT is 20-130°C (68-266°F).
  • The TCC is ON for 5 seconds.
  • The TCC is at maximum apply for 5 seconds.
  • The TCC slip speed is greater than 130 RPM.
  • All conditions met for 7 seconds

Action Taken When the DTC Sets

  • The VCM inhibits TCC engagement.
  • The VCM commands maximum line pressure.
  • The VCM inhibits 4th gear if the transmission is in hot mode.
  • The VCM freezes shift adapts from being updated.
  • The VCM illuminates the Malfunction Indicator Lamp (MIL).
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