Car electrical check
Materials and equipment:
* Multimeter
* Screwdrivers
* Safety glasses
*Insulating tape or heat shrink tubing
* Fuse set
*Car wiring diagram
Verification procedure:
1. Battery check
*Measure the voltage at the battery terminals using a multimeter. It should be around 12.6 volts when fully charged.
* Perform a load test on the battery using loads such as the starter or cigarette lighter. During testing, the voltage should not drop below 9 volts.
2. Checking the generator
* Start the engine and turn on all accessories such as lights, air conditioning and radio.
*Measure the voltage at the battery terminals using a multimeter. It should be in the range of 13.5 to 14.5 volts.
3. Checking the starter
* Make sure the vehicle is turned off and the gearshift lever is in park.
*Connect the positive terminal of the multimeter to the positive terminal of the starter, and the negative terminal to the negative terminal of the battery.
* Have an assistant turn the key to the start position.
* The multimeter should show a current of about 200-300 amperes.
4. Checking the ignition system
* Using the wiring diagram, check the resistance of the ignition coil. It must correspond to that specified in the vehicle’s owner’s manual.
* Check the gap between the spark plugs and the ignition coil tip. It must be as specified in the manual.
5. Checking electrical circuits
* Use a multimeter to check the resistance of various electrical circuits such as lights, turn signals and windshield wipers.
* The resistance value should be low, usually in the range of 0-10 ohms.
* Check the fuses for blown fuses and replace defective fuses with new ones of the same rating.
6. Grounding check
* Make sure all ground points are clean and securely connected.
* Measure the resistance between the ground points and the negative terminal of the battery. It should be close to zero.
Safety Tips:
*Always wear safety glasses when working on electrical components.
* Disconnect the negative terminal of the battery before starting work.
* Do not work on electrical components while the engine is running.
* Insulate all exposed wires with electrical tape or heat shrink tubing.
*If you are unsure how to perform any procedure, consult a qualified mechanic.