aaaa logo

Member of Australian Automotive Aftermarket Association

PRTC Council Member

4WD Council Member

Latest News

Ignition Distributors

Over the past years the common automotive vehicle ignition system has evolved from a points ignition distributor to the current distributor less Coil-over-plug system. Even though the Coil-over-plug system has been fitted to vehicles for a while now, a large percentage of vehicles still on the road are fitted with distributors utilising electronic ignition principals and still requiring diagnosis, testing, repair or replacement.

What the Technician Needs to know about the Electronic Ignition distributors:

  • A distributor generally integrates one or more inductive pick up coils to switch the ignition module ON and OFF or digital sensors to signal the ECU to switch the module ON and OFF. These are Generally known as the crank angle sensor, pick up coil or cylinder position sensor, depending on the type of system that it controls. This is required by the Technician for correct testing and diagnosis procedures.

  • An “ignition module” or “power transistor” may also be integrated in the distributor. Note: The “module” receives a signal from a pick-up-coil and directly switches the ignition coil ON and OFF to create the HT spark.
  • The “power transistor” receives a signal from the ECU and switches the Ignition coil ON and OFF to create the HT spark.
  • An Ignition coil may be located internal or external of the distributor.
  • These can become problematic and create a week or failing HT spark that dramatically affect the drivability of the vehicle.
  • Ageing distributors can create many unusual operating conditions such as excess noise, misfiring and oil leaks that requires the Technician to determine if it is financially viable to repair or preferably renew the distributor.

Common faults and testing procedures.

Testing procedures and test equipment vary depending on the type of distributor fitted to the vehicle and the type of fault that has occurred.

Typical test equipment used

  • Multimeter for voltage and Ohms reading tests if applicable
  • Suitable Oscilloscope for sensor and output tests.
  • Spark gap tool to monitor spark condition.

Areas to investigate when a low or no spark condition is evident;

  • Low or no voltage at the primary terminal of the ignition coil.
  • Negative terminal at the Ignition Coil not being pulsed by the ignition module or power transistor.
  • Faulty pick-up-coils or crank angle sensor.
  • Distributor cap and rotor faults or HT leads excessively open circuit.
  • Fault in ECU circuit if applicable system.
  • Ignition coil weak.

Typical Example of Testing. (Honda)

Honda distributor with three internal inductive pick-up-coils and an internal ignition module and ignition coil.

Method: Using a suitable Oscilloscope and back probing the 3 sensors. A Multimeter may be used for testing static voltage supply for ignition module and ignition coil.

Checking signal strength for:    

  • Cylinder sensor – 1 pulse every 2 crankshaft revolutions
  • TDC sensor – 4 pulses per 2 crankshaft revolutions.
  • Crank Angle Sensor – 24 pulses per 2 crankshaft revolutions.

All these signals are monitored by the ECU for Spark and injection timing and control. If all signals are acceptable, the ECU should trigger the distributor ignition module which intern switches the ignition coil ON and OFF to create the HT spark which is distributed to the relevant cylinders as required.

Typical Example of testing a distributor with integrated dual HALL sensor and power transistor. (Mazda V6)

Method: Using a suitable Oscilloscope and back probing the HALL sensor signals and ECU trigger for the power transistor / igniter. A Multimeter may be used for testing static voltage supply for all power supplies for Ignition coil and HALL sensors.

Note: A common “no spark condition” may be caused by a power transistor/ Igniter (integrated in the HALL sensor assembly) failure. Checking the signal from the ECU to “Terminal A“ whilst cranking, will quickly allow the Technician to rule out a variety of possibilities.

A suitable pulse at this point indicates that the CAS signals are functioning, and the ECU is switching the igniter as required.
Testing for a signal at the “TACHO“ terminal 2 will now determine if the Ignition coil or Igniter are faulty.

A suitable signal at the TACHO terminal indicates that the igniter is switching ON and OFF and further attention is required to the Ignition coil. No signal at the TACHO terminal indicates that there generally is a failure in the power transistor/Igniter.       

Again, depending on the condition and age of the distributor, it may be more economically viable to replace rather than to repair the complete unit. There are of course many other distributor configurations, but these typical test procedures should allow the Technician to quickly determine the next plan for attack.                                                                       

The Premier Auto Trade Ignition Distributors (DIS) program now includes almost 150 part numbers covering 1 million vehicle applications in Australia and NZ.


Latest News

Tech Tips - Wheel Speed Sensors (WSS)

Positive Crankcase Ventilation (PCV) and Oil Separators

Common Rail Diesel Pumps (HDP)

Exhaust Gas Temperature Sensor (EGT)

Hose Clamps

MAP Sensors (Manifold Absolute Pressure)

Electric Water Pumps

Pulse Width Modulation (PWM)

Mass Air Flow Sensors (Hot Wire/Film)

Petrol Fuel Injector Replacement

Electronic Throttle Bodies (TBO)

Dual Petrol Injection Systems – Technical Tip

Wheel Speed Sensors – More than just ABS

PAT Expands Emission Sensor Range

PAT Racing & Performance Injector Range Upgrade

Coils ain’t Coils!


Oil Level and Oil Temperature Sensors Operation

Failed Air Temperature Sensors Symptoms

MAP Sensors Testing

TI Automotive Mustang Performance Pump

New ICON SERIES Hose Clamp Range

New Premium Sensors Ranges

Relay problems on vehicle

Test Equipment and Tools

Fuel Rail Sensors (FRS)

Failing Secondary Ignition

Testing Electric Fuel Pumps

Performance Fuel Rails and Filters

Testing CAM Angle Sensors (CAM)

Testing Electric Valve Solenoids (EVS)

Electronic Throttle Bodies

Performance Fuel Cells & Surge Tanks

Fault Finding Fuel Pressure Regulators (FPR)

Testing Variable Camshaft Actuators (VCA)

Testing Accelerator Pedal Position Sensors (APS)

Diagnosing Crank Angle Sensors (CAS)

Performance Regulators and Gauges

Differentiating Wheel Speed Sensors (WSS)

Mass Air Flow Sensors - Hot Film

Mechanical Fuel Pumps (MFP)

ICON Series Hoses

Particulate Matter Sensors (PMS)

Performance Fuel Injectors

Fuel Injectors (GDI)

DENSO Spark Plugs

Performance Fuel Pumps

Cooling Fan Switches (CFS)

Water Temperature Sensors (WTS)

Reverse Light Switches

Oil Temperature Sensors (OTS)

BMC Air Filters

Flasher Cans

Exhaust Pressure Sensors (EPS)

Power Steering Switches

Coolant Temperature Sensors (CTS)

Variable Intake Manifolds (VIM) and Intake Control Valves (ICV)

Oil Level Sensors (OLS)

Throttle Position Sensors (TPS)

Air Temperature Sensors (ATS)

Ignition – Condensers, Contact Sets, Distributor Caps and Rotors

Fuel System Accessories (FSA)

MAP Sensors (MAP)

Relays (REL)

HALL Sensors and Pickups (HAL)

Fuel Rail Sensors (FRS)

Speed Sensors (SPS)

New ICON Series Fuel Pump Range

New ICON Series Hose Range

Performance Range Increase Continues

PAT Oxygen Sensor Range Expands

PAT Expands Automotive Aftermarket Presence

Equipment and Tools

Electric Fuel Pumps (EFP)

Electric Valve Solenoids (EVS)

CAM Angle Sensors (CAM)

Ignition Modules (MOD)

Injector Service Components

Exhaust Gas Temperature Sensors (EGT)

Throttle Bodies

Knock Sensors

Ignition Coils

Fuel Injectors (Petrol)

Variable Camshaft Actuators (VCA) Oil control Valves

Accelerator Pedal Position Sensors (APPS)

Exhaust Gas Recirculation Valves (EGR)

Relocation of Sydney Distribution Centre

Wheel Speed Sensors (WSS)

High Tension - Ignition Lead Sets (ILS)

Suction Control Valves (SCV)

Mass Air Flow (MAF) Sensors

Crank Angle Sensors (CAS)

Fuel Pressure Regulators (FPR)

Oil Pressure Sensors

Exhaust Gas Oxygen Sensors

Shedding Light on Stop Light Switches

Ignition Distributors

Common Rail Diesel (CRD) Fuel Injectors

Idle Speed Control

New Distribution Centre Opening in ADELAIDE

New Distribution Centres Opening in PERTH and DARWIN

New Fuel Catalogue from Premier Auto Trade

BMC 4WD Air Filters Range Expands

New MVP Fuel Injector Range

PAT Developing Programs on Demand

New Premium Packaging for PAT

New Product Ranges Released By PAT

PlusQuip Test Equipment Range Expands

New Raceworks Catalogue

New Exhaust Gas Temperature Sensors

New Trade Catalogues from Premier Auto Trade

New Distribution Centre Opening in Adelaide

More European Parts from Premier Auto Trade

New PlusQuip Fuse Current Tester

PAT Pumped up!

Coils ain't Coils!

New PlusQuip Electronic EGR, Throttle Body, and Actuator Tester

New breed of High Performance products!

New Ignition Coil and Lead Set Kits

Wheel Speed Sensor Program Launched

Premier Ignition Lead Program Launch

Ignition Coils - Coils ain't Coils!

PlusQuip Battery Testers Launch

Premier Auto Trade Supporting Local Racing

Oval Trumpet Airbox (OTA) for 4WD applications from BMC Air Filters

BMC Air Filters NOW AVAILABLE from Premier Auto Trade

Premier Ignition Coils

MAP-013 and KNS-021 Now Back in Stock

BMC Air Filter partners with Premier Auto Trade

Premier Auto Trade opens South Australian Distribution Centre

Direct Fit Oxygen Sensor Range Hits 700

Automotive Electro-Mechanical Relays Types / Faults / Diagnosis

PlusQuip Tools and Equipment Launch

PlusQuip Fuel Line Repair Kit

PlusQuip Fuel Injector Service Kit

E85 High Performance with Premier Auto Trade

Testing EGR Systems (Pt 2)

New Delphi Fuel Module and Ignition Coil Range

Fuel Injector Service Components from Premier Auto Trade

Older News...

   privacy statement   terms of use   terms and conditions   sitemap   news  

© PremierAutoTrade