What you likely need to do depends on what's wrong with your truck. To help you, I need more information. What problem are you trying to solve by "resetting the computer"? For example, are you experiencing:
* Check Engine Light: This requires diagnosing the problem using a code reader. Resetting the light without fixing the underlying issue won't solve anything.
* Electrical Problems: This could be caused by a variety of issues, and a simple reset won't always fix it.
* Performance Issues: Again, a diagnosis is needed to identify the cause.
* Radio Issues: This usually involves a separate reset procedure for the radio itself.
To try a simple reset of some of the electronic modules (this doesn't work for all issues):
1. Disconnect the battery's negative terminal: Use a wrench to loosen the clamp and remove it from the battery post.
2. Wait: Leave the negative terminal disconnected for at least 30 minutes (some people recommend up to an hour). This allows the capacitors in the modules to discharge.
3. Reconnect the negative terminal: Securely attach the negative terminal clamp back to the battery post.
4. Start the truck: See if the problem is resolved.
If this doesn't work, you will likely need:
* OBD-II scanner: To read diagnostic trouble codes (DTCs) from the ECM. This will help pinpoint the source of the problem.
* Professional Mechanic: If you're uncomfortable diagnosing and fixing car problems, take it to a qualified mechanic. They have the tools and expertise to properly diagnose and repair the issue.
Be specific about the problem you're experiencing, and I can offer more tailored advice.