More than likely there is a connection issue with the interface card under the floor plate at right hand side. Lift it out and remove the cover and check the connectors. sometimes just unplugging them and re-fitting does the trick.

Hi,

Let try the following ways:

Error 68 means :

- Safety switch (seat switch or deadman sw,..) wire breakage
=> Let check wire connection to Safety switch (seat switch or deadman sw,..) or check the function of the seat switch or deadman sw,..

If not, let tell me more information :

- Your truck was born on 2004 but what month ? before 08/2004 or after 08/2004
- Your truck is AC technology or DC ?
- You email address ?

Then I will help you more.

Good luck