Contents: Wiring Color Codes ↳ Voltage checks ↳ Definition of short circuit ↳ Grounding check ↳ Testing electrical conductivity ↳
To make it easier to identify electrical defects, wiring diagrams are provided at the end of the book.
Wiring Color Codes
When looking at wiring diagrams, use the following alphabetical code to determine the color of the wires you are testing:
- B - black
- BR - brown
- DB blue
- DG - dark green
- GY - gray
- LB - blue
- LG - light green
- N - natural
- (N) strokes
- O - orange
- R - purple
- RK - pink
- R - red
- T - reddish brown
- W - white
- Y - yellow
Note: the presence of marks on the wire is indicated by a second color "H" - for dashes or "D" - for dots. If there is no letter designation, stripes are implied.
If several components or circuits fail at the same time, the problem is most likely in the fuses or ground, since often several circuits are shorted to one fuse or one ground. Visually inspect the condition of all fuses, wires, contacts in the suspect circuit before diagnosing it.
The basic tools needed to diagnose electrical circuits are a tester, a high-impedance (10k ohm) digital voltmeter, a continuity tester, and connecting wires with an internal circuit breaker for the constituent electrical components. Before determining the location of a circuit break or the cause of its failure using electrical testing tools, you should decide where to make the necessary connections using a wiring diagram.
Voltage checks
If the circuit does not function normally, first check the voltage.
Note: Remember that some circuits are only energized when the ignition key is turned to the "on" or "ready to go" position.
Definition of short circuit
Remove the fuse and connect a voltmeter or test light instead. There will be no voltage in the circuit. While watching the test light, move the wires from side to side.
If the light comes on, it means there is a short circuit somewhere.
Grounding check
To check if the element is properly grounded, a circuit test must be performed.
Testing electrical conductivity
A conductivity test determines whether the circuit is open (conducting electricity). When the circuit is off (no voltage), the conductivity test can be performed using a tester with an automatic power source.
(The original source of this article can be found at: FORDBOOK)