*cruise control self test

Enter self-test diagnostics by depressing the speed control OFF switch while turning the ignition key ON, making sure the engine does not start and is not running. The speed control indicator on the instrument panel
will flash once to indicate that speed control module entered the diagnostic mode. Five additional flashes at this point indicate a defective speed control servo. Release the OFF switch.
Press the remaining switches in this sequence: ON, RESUME, COAST and SET/ACCEL.
If the ON switch is not depressed within five seconds after entering the diagnostics mode, the module times out and the procedure must be started over.
The speed control indicator lamp will flash as each switch is depressed. Press each switch in the sequence immediately after the indicator light goes out for the previous switch.
NOTE: There will be a slight delay when the last button is pressed and the lamp flashes.

A lamp flash with the last button (SET/ACCEL) indicates that the static test passed. If the lamp does not flash with the last button and there are no additional flashes of the lamp, the switch is defective.
If the lamp does not flash with the last button, and additional flashes occur, follow the chart below for trouble codes:
2 flashes - BPP defective, circuit is defective, brake applied, CPP switch or jumper (if equipped).
3 flashes - deactivator switch is open or circuit defective.
4 flashes - vehicle speed signal is out of range or circuit is defective
Immediately (.25 second delay) after the static test, the speed control servo does a dynamic test by automatically actuating the throttle lever from 8 mm (0.315 in) to 12 mm (0.472 in) of travel from the idle position. During the dynamic throttle pull, observe throttle movement to witness any binding or sticking of the speed control cable and correct connection of speed control cable to throttle lever. Make sure the throttle returns to the idle position.

*check engine light self test

If the check engine light comes on and stays on, it is warning you there is a problem in the EFI system.
The check engine light is a self diagnosis system and has codes which you can access.
The information contained in the SBEC/SMEC can be accessed by you, using your ignition key! The mechanics use the DRBII(Diagnostic Readout Box) a very expensive tool which reads out the codes on a digital display terminal.
There is a description of these codes in the "Haynes Repair Manual" a must have source for all vehicle owners. These manual are based on a complete tear-down and rebuild of the vehicle. Haynes has manuals for most every make and model, be certain of the vehicles year, this is very important.
To access the codes using your ignition key:
1) with the engine on, set the parking brake in neutral (manual shift) or park (automatic)
2) watching the RPM gage in idle, raise it to approximately 2500 RPM and then slowly let it down again to normal idle.
(If you have air conditioning let it cycle on for a moment than turn it off.)
3) with an automatic transmission put your foot on the brake and shift through all the gears slowly and then back to park again. (This allows the computer to access any fault codes, including those linked to the any of the sensors controlled by the transmission.) Stop the engine.
4) To display the codes on the check engine light you must,
turn the ignition key ON (not the engine!) then OFF, ON, OFF and finally ON. The codes will begin to flash on the check engine light. The light will blink the number of the first digit then it will pause and blink the number of the second digit.
For example: Code 42, would be indicated by 4 flashes followed by a pause and then 2 flashes.
At times more than one code will flash depending on what was diagnosed so it is wise to have a pen or pencil handy to write down the number of flashes to be certain.
Once the code is obtained refer to the Haynes Manual written for your vehicle, it will have a list of the trouble codes and a brief description of the problem, such as a sensor or a circuit malfunction. With this information you should be able to diagnose the problem yourself and take the necessary measures to have it repaired and/or replaced.
Please note, it is possible a particular fault code that is monitored by the engine computer will not be entered into the memory despite a malfunction. This can happen when certain fault code criteria is NOT met.
If the check engine light is on and staying on, there IS a PROBLEM.
If you don't want to try and diagnose it using the information provided; I would suggest going to a different mechanic and asking them to perform the test. It is not expensive and it may save you some money in the long run.
It is always wise to ask for and get a second opinion.