Automotive Service Excellence (ASE) A6 Electrical/Electronic SystemsGeneral Electrical/Electronic System DiagnosisEasy
A technician is using service information to troubleshoot an intermittent fault with a vehicle's exterior lighting system. The wiring diagram shows wires identified by a combination of letters and numbers, such as 'L/G' or 'BRN/WHT'. What do these annotations MOST commonly represent?
- AThe circuit number and component identification.
- BThe gauge (thickness) of the wire.
- CThe primary and secondary colors of the wire insulation.
- DThe voltage level and current capacity of the wire.
Show answer & explanationAnswer & explanation
Correct answer: C. The primary and secondary colors of the wire insulation.
In automotive wiring diagrams, a combination of letters like 'L/G' (Light Green) or 'BRN/WHT' (Brown with a White stripe) is the standard convention for indicating the color of the wire insulation. The first letter(s) represent the primary color, and the second letter(s) (after a slash or hyphen) represent the stripe color.
Why the other options are wrong
- A. Circuit numbers and component IDs are usually separate alphanumeric designations, not combined with color codes.
- B. Wire gauge is typically indicated separately, often numerically (e.g., 18 AWG).
- D. Voltage level and current capacity are properties of the circuit and wire, not typically represented by these color annotations.
Wiring Diagram Color Codes
In automotive wiring diagrams, alphanumeric codes like 'L/G' or 'BRN/WHT' represent the primary and secondary (stripe) colors of the wire insulation, used for identification and tracing circuits.
- First letter(s) = primary color.
- Second letter(s) = stripe color (if present).
- Crucial for physically identifying wires during diagnosis.
Memory trick: Letters and slashes, colors they flash, for wiring's true dash.