Ignition Coil Resistance
- Coil is designed to operate with an external ballast resistor. When testing coil for output and resistance, also make resistor tests. Also inspect coil for external cracks and arcing.
- To check coil primary resistance, isolate coil from rest of system. A Connect ohmmeter leads to positive and negative primary terminals. To check secondary resistance, connect ohmmeter leads to coil negative terminal and coil tower.
- If resistance readings are not to specifications, replace ignition coil.
Resistance Specifications
| Application | Ohms@70-80°F | |
|---|---|---|
| Primary Resistance | ||
| Prestolite | 1.60-1.79 | |
| Essex | 1.34-1.55 | |
| Secondary Resistance | ||
| Prestolite | 9400-11, 700 | |
| Essex | 9000-12, 200 | |
| Single Ballast Resistor | ||
| Resistor Resistance | 1.12-1.38 | |