Test TP - Throttle Position Sensor

NOTE: To diagnose throttle position on 1.8L with manual transaxle, see CIRCUIT TEST STG. Enter this test only when a Code 12 is displayed during SELF-TEST procedure, or when directed here from another CIRCUIT TEST. To prevent replacement of good components, check the following non-EEC components for fault: idle speed or throttle stop adjustments, throttle shaft or linkage, and cruise control linkage.

Fig 1: Identifying TP Connector Terminals

CIRCUIT PIN IDENTIFICATION

Circuit	Breakout Box Pin	ECA Pin
1.8L (ATX)
IDL	18	1N
SIGRTN	46, 49	2D
TP	18	1N
VREF	26	2K
1.8L (MTX)
SIGRTN	46, 49	2D
IDL	18	1N
WOT	27	2L
2.2L (Non-Turbo MTX)
SIGRTN	46, 49	2D
TPS	47	2M
VREF	26	2K
2.2L (Non-Turbo ATX)
SIGRTN	46, 49	3D
TPS	47	2F
VREF	26	2I
2.2L (Turbo)
SIGRTN	46, 49	3D
TPS	47	2F
VREF	26	2I

1) Checking System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to step 2).

2) Checking TPS Voltage Ensure engine is at operating temperature. With ignition off, install breakout box. Turn ignition on. Measure voltage between TPS and SIGRTN test pins. Slowly depress accelerator pedal and compare voltage to specifications shown in VOLTAGE & RESISTANCE SPECIFICATIONS (TP SENSOR) . If voltage is within specification, TPS circuit is okay; fault is in another circuit or ECA. If voltage is not within specification, go to step 4).

3) Checking TPS Signal Return Remove TPS connector. Using jumper wire, attach SIGRTN and VREF connector terminals to TPS sensor. Attach voltmeter between sensor TPS terminal and SIGRTN terminal. Turn ignition on. Slowly depress accelerator pedal and compare voltage to specifications shown in VOLTAGE & RESISTANCE SPECIFICATIONS (TP SENSOR) . If voltage is as specified, repair TPS circuit between ECA and TPS. If voltage is not as specified, go to step 4).

4) Checking SIGRTN/VREF At TPS Remove TPS connector. Turn ignition on. Measure voltage between TPS wire and SIGRTN wire. If voltage is 4.5-5.5 volts, adjust or replace TPS. If voltage is not 4.5-5.5 volts, go to CIRCUIT TEST VREF.

VOLTAGE & RESISTANCE SPECIFICATIONS ⁽¹⁾

Throttle Position

Ohms

Volts

1/8 Open

.998

.989

1/4 Open

1.104

1.60

3/8 Open

1.278

2.37

1/2 Open

1.462

2.74

5/8 Open

1.480

3.15

3/4 Open

1.459

3.43

7/8 Open

1.144

3.60

Full Open

1.072

4.02

⁽¹⁾	Values may vary by 15 percent.