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Testing Precautions

  1. ALWAYS turn ignition switch off, or disconnect battery for resistance tests. ALWAYS disconnect the engine speed/reference sensor for compression tests. If this is not done, dangerous high voltages and insulation damage to the following components may result: ignition coil, high-voltage distributor and ignition leads.
  2. NEVER  connect a capacitor to ignition coil terminals. NEVER  connect ignition coil terminal No. 1 to ground. The ignition coil and DME control unit could be damaged.
  3. NEVER  connect battery leads or test light to ignition coil terminal No. 1. The DME control unit will be damaged. NEVER  disconnect ignition lead from ignition coil secondary terminal during engine operation.
  4. Voltage flashover from ignition coil secondary terminal to ignition coil primary coil terminals (No. 1 and 15) must be avoided. The DME control unit could be damaged.
  5. When testing, the secondary circuit of the ignition system MUST be suppressed at all times with 4000-ohm resistance (1000-ohm distributor cap suppression resistor; 3000-ohm spark plug lead suppression resistors).
  6. ALWAYS turn ignition switch off or disconnect battery BEFORE disconnecting ignition or DME control unit connectors. Electrostatic discharge may damage DME control unit.
  7. NEVER  disconnect battery while engine is running. Reversed battery polarity could damage ignition or DME control unit. DO NOT  exceed a charging voltage of 16 volts (including when using a battery charger).
NOTE: Complete system and component testing information is not available from manufacturer. Only components with informations available are covered in this article.
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