aaaa logo

Member of Australian Automotive Aftermarket Association

PRTC Council Member

4WD Council Member

Latest News

Accelerator Pedal Position Sensors (APPS)

What the Technician needs to know about the Accelerator pedal position sensors on a Drive by wire system.

There are generally two operating system types of APPS units that have been used utilised by manufacturers on the Link-less type – Electronic Throttle - Drive by wire system).

1. Potentiometer – contact type APS dual operating units with both output signals monitored by the ECM.

Note:  The APPS is “generally” located on the accelerator pedal. This is not always the case as many vehicles utilised an accelerator cable from the pedal to operate a separately mounted APPS in the engine bay (Mercedes - early models) or integrated in the throttle body itself. (Nissan Patrol).

The BA/BF Falcon range utilise a triple APPS integrated in their accelerator pedal assembly. The dual or triple APPS units are required to ensure a more accurate and safer throttle operation.

2. HALL sensor- Contactless type APPS units with either analogue or PWM output signals monitored by the ECM.

These units are widely used in all vehicle types from motor vehicles to heavy trucks and plant equipment. No physical internal contact ensures a greater operating accuracy in heavy vibration and dusty conditions.

Typical Toyota dual HALL sensor APPS – Analogue output type (varying voltage).

Note: Generally, the output voltages or signals will not be identical on Petrol vehicles “but” there are Diesel vehicles with identical APPS outputs. (Mazda BT-50)

What are some of the effects on a vehicle when an APPS malfunctions?

When the APPS signal/s are incorrect, the Electronic Throttle system will convert to default mode – causing:

  • Check engine light on and fault code logged. Examples - P0121 Accel Pedal Sensor 1 Circuit performance / P1125 Accel Pedal Sensor.
  • The throttle valve may be held in the default position, limiting engine RPM and road speed to a minimum. This is generally felt as a lack of power during acceleration. In some cases, this condition may create forced shut down and result in engine stall.
  • Other systems may be affected such as transmission shifting and gear selection.
  • Message displayed on dash indicating “Reduced Engine Power” – Depending on vehicle.

APPS Typical test procedures.

It is important to determine if the APPS is actually faulty, or as in many cases, external factors have created the problem. Whether a contact type or contact less type, the pre-test procedure is similar.

Are all power supplies and grounds correct? Note: Many an APPS has been renewed only to find that a power supply or ground was the cause.

Is the test equipment adequate for testing to be carried out?

  • Suitable scanner
  • Digital Multimeter for Voltage readings.
  • Suitable oscilloscope – operational sweep (either analogue or digital signal)

Contact type APPS test.

Contactless type APPS test.     


Accelerator Pedal Released Position Learning.

Disconnecting an APPS or ECM may require an APPS pedal position relearn. Refer vehicle specifications if unsure is required for specific vehicle.

A typical Nissan procedure is:

  1. Ensure accelerator pedal is fully released.
  2. Switch IGN ON and wait for at least two seconds.
  3. Switch IGN OFF and wait for at least ten seconds.
  4. Switch IGN ON and wait for at least two seconds.
  5. Switch IGN OFF and wait for at least ten seconds.

The Premier Auto Trade Sensors range includes Accelerator Pedal Position Sensors that cover over 1.2 million vehicle applications in Australia and NZ.

When you supply and fit products from Premier Auto Trade you can expect a product designed and tested to the vehicle manufacturer’s specifications offering OE form, fit and function. Premier Auto Trade distributes products throughout Australia via a network of specialised resellers and leading automotive groups.


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