6-Pin Throttle Position Sensor Wiring Diagram

6-Pin Throttle Position Sensor Wiring Diagram — interactive diagram. Open it in the editor to customise components and wiring.

This is a free printable 6 pin throttle position sensor wiring diagram: download the diagram as SVG or open it and print to paper or PDF.

A 6-pin throttle position sensor (TPS) wiring diagram shows two sets of reference voltage, signal, and ground connections for a dual-track potentiometer sensor used on drive-by-wire throttle bodies to provide redundant position feedback to the ECU.

A throttle position sensor (TPS) converts the mechanical position of the throttle plate into an electrical signal the engine control unit (ECU) reads to calculate the correct fuelling, ignition timing, and idle control. On drive-by-wire (electronic throttle control) systems, the TPS is part of the throttle body actuator assembly and uses dual redundant tracks for safety.

WHY 6 PINS ON A DUAL-TRACK TPS? A basic 3-pin TPS uses: 5 V reference (Vref), signal output, and ground. A 6-pin TPS doubles this for two independent sensor tracks: - Track 1: Pin 1 = 5 V reference; Pin 2 = signal output 1; Pin 3 = ground - Track 2: Pin 4 = 5 V reference; Pin 5 = signal output 2; Pin 6 = ground

The two signal outputs produce inverse or offset voltage curves relative to throttle position. At closed throttle (idle), Track 1 might read ~0.5 V while Track 2 reads ~4.5 V. At wide-open throttle, Track 1 reads ~4.5 V and Track 2 reads ~0.5 V. The ECU continuously compares both signals — if they deviate from their expected relationship by more than a calibrated threshold, the ECU logs a fault code and may enter limp-home mode or shut the throttle.

PIN IDENTIFICATION: Pin numbering and functions vary significantly between manufacturers. On some sensors the 5 V reference for both tracks shares a common pin, making it a 5-pin rather than 6-pin connector. Always confirm the specific pinout from the vehicle's service data or by measurement — do not assume pin order from visual inspection.

MEASUREMENT METHOD: With the ignition on (engine off), measure each signal pin relative to sensor ground with the throttle plate at rest. Track 1 signal should read 0.4–0.8 V at idle and Track 2 should read 4.2–4.6 V (or the inverse, depending on the sensor design). Slowly open the throttle and confirm both signals change smoothly without dropouts or flat spots. Any flat spot in the signal sweep indicates a worn track on the potentiometer.

NOTE ON ELECTRONIC THROTTLE BODIES: On drive-by-wire systems, the TPS is incorporated into the throttle actuator assembly and is not separately replaceable in many applications — the entire throttle body must be replaced if the sensor tracks wear.

How to wire 6 pin throttle position sensor wiring diagram

Obtain the vehicle-specific TPS connector pinout Before measuring or replacing the sensor, locate the vehicle's wiring diagram for the throttle position sensor connector. Pin 1 may be at the left or right end of the connector depending on viewing direction — the diagram will specify orientation.
Set the multimeter and verify the 5 V reference With ignition on and engine off, set the multimeter to DC millivolt/voltage mode. Probe each pin of the TPS connector relative to the sensor ground pin. Identify which pins show approximately 5 V — these are the reference voltage pins for each track.
Identify the two signal output pins The signal pins will show voltages between 0.4 V and 4.6 V at closed throttle. Both should be present and within expected range. Measure both relative to their respective ground pins or a common ground if the grounds are shared.
Perform a throttle sweep test With the sensor connected and ignition on, slowly open the throttle plate from closed to wide-open (manually on cable-operated throttles; use a scan tool live data on drive-by-wire systems). Both signal outputs must sweep smoothly without dropouts, flat spots, or erratic jumps.
Check ground pin resistance to chassis With ignition off, measure resistance from each TPS ground pin to a known chassis ground. Resistance should be less than 1 ohm. High ground resistance produces a false high signal reading — the sensor appears to read open throttle at idle.
Verify the 5 V reference at the ECU if sensor readings are abnormal If signal voltages are absent or abnormal despite the sensor appearing intact, measure the Vref pin at the ECU harness (ignition on). If Vref is low at the ECU, there is a short to ground on the sensor wiring or a faulty ECU internal regulator — do not replace the TPS until the Vref issue is resolved.
Replace and calibrate if required If the TPS is confirmed faulty, fit a replacement sensor of the correct specification. Some vehicles require a TPS reset or idle air control calibration using a scan tool after replacement — check the service manual for the specific procedure.

Specifications

Reference voltage (Vref) per track	5.0 V ± 0.1 V (ECU-supplied)
Signal output — Track 1 at closed throttle (typical)	0.4–0.8 V
Signal output — Track 1 at wide-open throttle (typical)	4.2–4.6 V
Signal output — Track 2 at closed throttle (typical)	4.2–4.6 V (inverse to Track 1)
Signal output — Track 2 at wide-open throttle (typical)	0.4–0.8 V (inverse to Track 1)
Sensor type	Dual-track potentiometer or dual Hall-effect (non-contact)
Connector	6-pin weatherproof automotive connector (type varies by manufacturer)
Fault code for correlation failure	P2135 (Track 1 / Track 2 correlation out of range)

Safety warnings

A faulty TPS on a drive-by-wire vehicle can cause unintended acceleration or loss of throttle control. Do not operate a vehicle with a known TPS fault — address the fault before driving.
Do not supply an external voltage source to any TPS pin. The 5 V reference must come from the ECU only. Applying 12 V to the Vref or signal pin will destroy the sensor and may damage the ECU input circuit.
When probing TPS pins with the connector in place (back-probing), use a fine-tipped probe to avoid spreading connector pins. Spreading or bending pins in the ECU connector causes intermittent faults that are difficult to diagnose.
After any replacement of a TPS or throttle body on a drive-by-wire vehicle, perform the manufacturer's specified idle learn and throttle position calibration procedure. Skipping this step can cause idle instability, rough running, or continued fault codes.
Verify that the replacement TPS matches the exact sensor specification for the vehicle. An incorrect sensor with a different output voltage range or different track relationship (same-direction vs inverse tracks) will cause persistent ECU fault codes and may not allow the engine to run.

Tools needed

Digital multimeter with DC millivolt resolution
Automotive scan tool (for live data and fault code reading)
Back-probing pins or piercing probes (fine-tipped)
Wiring diagram or service manual for the specific vehicle
Contact cleaner (for connector cleaning)
Dielectric grease (for reconnected connector pins)

Common mistakes

Measuring TPS signal voltage relative to chassis ground rather than the sensor's own ground pin — a small resistance difference in the sensor ground circuit causes a voltage offset that looks like a sensor fault.
Replacing the TPS before verifying the 5 V reference is correct — if the Vref is low due to a short on the sensor wiring, a new TPS will produce the same abnormal readings.
Ignoring a P2135 correlation fault and only addressing the P0120-series codes — the correlation code is the most specific indicator of a dual-track failure and should be the primary diagnostic target.
Swapping the two signal output wires at the ECU connector — this causes both tracks to appear to move in the same direction rather than inverse directions, triggering a P2135 immediately on start-up.
Fitting a non-OEM TPS with a slightly different voltage range — even a 0.2 V offset in the idle position can be enough to set a range fault code or cause poor idle quality.

Troubleshooting

P2135 — TPS correlation fault between Track 1 and Track 2: Cause: The two signal outputs are not tracking within the expected inverse relationship — one track has a dropout, flat spot, or total failure. Fix: Monitor both signal voltages simultaneously on a scan tool while sweeping the throttle. Identify which track shows irregular behaviour. Confirm sensor ground and Vref are good. If one track is flat or erratic, the sensor is faulty — replace the TPS or throttle body assembly as required.
Both TPS signal pins read near 0 V or near 5 V regardless of throttle position: Cause: 5 V reference is missing (short to ground on Vref line), or both signal wires are shorted to ground or Vref. Fix: Disconnect the sensor. Measure Vref pin at the harness connector (ignition on) — should read 5 V. If 0 V, the short is on the harness side or at the ECU. If 5 V is restored with sensor disconnected, the sensor itself is short-circuiting the Vref.
Flat spot or dropout in one TPS signal during throttle sweep: Cause: Worn carbon track on the potentiometer in one of the two tracks. Fix: Confirm by monitoring live data during a slow, smooth throttle sweep. A momentary signal drop to near 0 V or near Vref during the sweep confirms a worn track. Replace the TPS or throttle body assembly.

Frequently asked questions

Why does a drive-by-wire TPS need two sensor tracks?

Redundancy is a safety requirement. If a single-track TPS fails, the ECU would have no position reference and could not control the throttle. With two independent tracks providing inverse signals, the ECU can detect a single sensor failure by comparing the two outputs. A failed track causes a discrepancy, triggering a fault code and safe-state response before a dangerous condition arises.

What voltage should I see on TPS signal pins with ignition on?

With ignition on and engine off at closed throttle, Track 1 typically reads 0.4–0.8 V and Track 2 reads 4.2–4.6 V (or vice versa, depending on the sensor design). At wide-open throttle, the values swap. Measure both signal pins relative to the sensor's own ground pin — not chassis ground — for accurate readings.

Can I clean a TPS to fix a dropout or flat spot in the signal?

Cleaning the potentiometer track with electrical contact cleaner can temporarily restore a poor signal on older external TPS units. However, physical wear of the carbon track cannot be cleaned away — replacement is the correct fix. On modern integrated electronic throttle body assemblies, the sensor is sealed and cannot be cleaned or serviced separately.

What fault codes are associated with a faulty 6-pin TPS?

Common codes include P0121–P0123 (TPS circuit low/high/range), P0220–P0223 (throttle position sensor 2 circuit), and P2135 (TPS correlation fault between Track 1 and Track 2). A P2135 specifically indicates the two signal tracks are not tracking within the expected relationship — this is the most diagnostic code for a dual-track TPS fault.

What happens if the 5 V reference voltage is absent or low?

If the 5 V reference (Vref) is missing or below ~4.5 V, both TPS signal outputs will be proportionally low and the ECU will log a fault. The Vref is generated by the ECU's internal voltage regulator — a short to ground on any sensor sharing that Vref line will pull the voltage down and affect all sensors on that reference rail.