2005-2006 Models

NOTE: Record all freeze data and review General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ) before you troubleshoot.

Check whether the HDS indicates another code.
Does the HDS indicate another code?
1. YES -Do the DTC Troubleshooting for the indicated code(s). Recheck for DTC P0780 after troubleshooting.
2. NO -Go to step 2.
Measure the stall speed RPM in the D position (see STALL SPEED TEST ).
Is the stall speed over 3,500 RPM?
1. YES -Replace the transmission.
2. NO -If the stall speed is below 2,000 RPM, replace the lower valve body assembly. If the stall speed is 2,000-3,500 RPM, go to step 3.
Drive the vehicle at 37 mph (60 km/h) constantly for several minutes, and check the engine speed with respect to vehicle speed (see ROAD TEST ).
Is the engine speed within specification?
1. YES -Replace the lower valve body assembly.
2. NO -Replace the transmission.