Test DH - Throttle Position Sensor (TPS)

NOTE: Perform this test when Code 23, 53, 63, or 73 is displayed during QUICK TEST.

Fig 1: TPS Circuits

Fig 2: TPS Specification Charts

THROTTLE POSITION SENSOR SPECIFICATIONS

TPS SETTING (KOEO & KOER)				TPS CIRCUIT (SIGNAL) VOLTAGE RANGE
Application	Rotational Degree Range	Voltage Range	Minimum	Maximum
2.3L OHC PFI	0-13.5°	.6-1.22	.20	4.84
2.3L HSC PFI	3-13.5°	.7-1.22	.20	4.84

NOTE: The normal range of throttle angle measurement for the TPS is 0 to 85 degrees. To pass QUICK TEST procedure, the range of throttle rotation (in degrees) must be within 3% of specification.

To prevent replacement of good components, be aware that the following non-EEC related areas may be at fault:

Idle speed
Throttle stop adjustment
Binding throttle shaft or linkage
Cruise control linkage

1) Code 23: Perform This Check Before Servicing This Code Code 23 indicates that the TPS rotational setting may be out of the Self-Test range. See specification chart. Possible causes for this fault are:

Binding throttle linkage
TPS not seated correctly
Faulty TPS
Faulty ECA

If you are at this step to service a KOEO Code 23, check for a Code 68. If you are at this step to service a KOER Code 23, check for Codes 31 or 58. If any of these codes are present, return to the KOEO or KOER Code Charts and proceed as directed to Codes 68, 31 or 58. If these codes are not present, go to next step.

2) Check For Stuck Throttle Plate Inspect throttle body and linkage for binding or sticking. Ensure linkage is in the throttle closed position. If throttle plate or linkage is binding, check for binding throttle or cruise control linkage, vacuum line or harness interference, etc. Repair any problem and repeat QUICK TEST. If no mechanical problem is found, go to next step.

3) Code 53: Attempt to Generate Code 63 Code 53 indicates that TPS signal is greater than Self-Test maximum value. Possible causes for this fault are:

TPS not seated properly
Faulty TPS sensor
VREF circuit shorted in vehicle harness
Faulty ECA

Turn key off and wait 10 seconds. Disconnect TPS from vehicle harness at throttle body. Inspect for and repair any damaged wiring or connector pins. Repeat KOEO Self-Test. Ignore all other codes at this time. If Code 63 is not displayed, go to step 6. If Code 63 is displayed, go to next step.

4) Check VREF Circuit Voltage Turn key off and wait 10 seconds. Set DVOM on 20-volt scale. Disconnect TPS and both 4EAT module vehicle harness connectors. With KOEO, measure voltage between VREF and SIG RTN at TPS vehicle harness connector. If reading is less than 4 volts or more than 6 volts, reconnect the sensor and go to TEST C, step 1. If reading is between 4 and 6 volts, replace TPS and repeat QUICK TEST.

NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 4 to step 6. No test procedures have been omitted.

6) Checking TP Circuit For Short to Power Turn key off and wait 10 seconds. Disconnect TPS from harness. Set DVOM on 200-k/ohm scale. Disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box, leaving ECA disconnected. Measure resistance between test pin No. 47 and test pins No. 26 and 57. If either reading is less than 10 k/ohms, repair short in harness, connect components and repeat QUICK TEST. If both readings are 10 k/ohms or more, replace ECA, reconnect components and repeat QUICK TEST.

NOTE: There is a break in the step numbering sequence at this point, skipping from step 6 to step 10. Break is due to previous chart references to these testing procedures. No test procedures have been omitted.

10) Code 63: Attempt to Generate Code 53 or 23 Code 63 indicates that TP signal is less than minimum Self-Test value. Refer to specification chart at beginning of this CIRCUIT TEST. Possible causes for this fault are:

TPS not seated correctly
Faulty TPS
Open circuit in vehicle harness
Grounded circuit in vehicle harness
Faulty ECA

Turn key off and wait 10 seconds. Disconnect TPS from harness. Install a jumper wire between VREF and TP circuit at TPS vehicle harness connector. Perform KOEO Self-Test. Check for Codes 53 or 23 (ignore all other codes at this time). If Codes 53 or 23 are not present, immediately remove jumper wire, and go to next step. If either Code 53 or 23 is displayed, replace TPS, remove jumper and repeat QUICK TEST.

11) Check VREF Circuit Voltage Turn key off and wait 10 seconds. Disconnect TPS from vehicle harness. Inspect for and repair any damaged wiring. Set DVOM on 20-volt scale. With KOEO, measure voltage between VREF and SIG RTN circuits at TPS vehicle harness connector. If reading is less than 4 volts or more than 6 volts, go to TEST C, step 1. If reading is between 4 and 6 volts, go to next step.

12) Check TPS Circuit Continuity Turn key off and wait 10 seconds. Leave TPS disconnected. Set DVOM on 200-ohm scale and disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box and connect ECA. Measure resistance between TP circuit at TPS vehicle harness connector and test pin No. 47. If reading is 5 ohms or more, repair open circuit. Remove breakout box, reconnect all components and repeat QUICK TEST. If reading is less than 5 ohms, go to step 20.

NOTE: There is a break in the step numbering sequence at this point, skipping from step 12 to step 20. Break is due to previous chart references to these testing procedures. No test procedures have been omitted.

20) KOER Code 73: Perform Correct Dynamic Response (Goose) Test at Wide Open Throttle (WOT) KOER Code 73 indicates that TPS did not exceed 25% of its rotation during Dynamic Response (Goose) Test. A complete WOT must be performed during Dynamic Response portion of KOER Self-Test.

Run KOER Self-Test, ensure WOT is performed during Dynamic Response portion of test. If Code 73 is still present, go to next step. If not, system is unable to duplicate Code 73 at this time. Service any other KOER codes at this time. If no other KOER codes are present, testing is complete.

21) Check TPS Movement During Dynamic Response Test Turn key off and disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box and connect ECA. Set DVOM on 20-volt scale. Connect DVOM between test pins No. 46 and 47. Perform KOER Self-Test and ensure a proper WOT is performed. Monitor DVOM reading during Goose Check. If reading exceeds 3.5 volts, replace ECA, remove breakout box, reconnect all components and repeat QUICK TEST. If reading does not exceed 3.5 volts, ensure TPS is correctly installed and adjusted. If okay, replace TPS, and repeat QUICK TEST.

NOTE: There is a break in the step numbering sequence at this point, skipping from step 21 to step 90. Break is due to previous chart references to these testing procedures. No test procedures have been omitted.

90) Continuous Memory Code 53: Monitor TPS Circuit Under Simulated Road Shock Conditions Using KOEO Continuous Monitor Mode (Wiggle Test), observe DVOM or diagnostic tester for indication of fault while slowly opening throttle to WOT. Slowly bring throttle to closed position, lightly tap TPS and wiggle harness connector. This test attempts to find an open or short in the TPS, connectors and vehicle harness. If no fault is indicated, go to step 92. If fault is indicated, go to next step.

91) Measure TP Circuit Voltage While Exercising TPS Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for and repair any damaged wiring. Install breakout box, leaving ECA connected. Stay in KOEO Continuous Monitor Mode (Wiggle Test) as in previous step. Connect DVOM between test pins No. 47 and 46. Set DVOM on 20-volt scale. With KOEO, observe DVOM and repeat step 90. If fault occurs at less than 4.25 volts, inspect TPS connectors and terminals. If okay, replace TPS, clear codes and repeat QUICK TEST. If fault does not occur at less than 4.25 volts, TPS over-travel may have caused Continuous Memory Code 53. TPS is okay, go to next step to check harness.

92) Check EEC-IV Vehicle Harness While in KOEO Continuous Monitor Mode, shake, bend and wiggle small sections of EEC-IV harness from TPS vehicle harness connector to firewall, and from firewall to ECA. If fault is indicated, isolate fault in wiring and repair as necessary. Clear codes and repeat QUICK TEST. If no fault is indicated, go to next step.

93) Check ECA & Harness Connectors Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect both connectors and terminals for obvious damage. If connectors and terminals are damaged, repair as necessary, clear Continuous Memory Codes and repeat QUICK TEST. If connectors and terminals are okay, fault cannot be duplicated at this time. Continuous Memory Code 53 testing is complete.

94) Continuous Memory Code 63: Monitor TP Circuit Under Simulated Road Shock Conditions Using KOEO Continuous Monitor Mode, observe VOM or diagnostic tester for indication of fault while doing the following:

Slowly open throttle to WOT
Slowly bring throttle to closed position
Lightly tap TPS and wiggle connector

This test attempts to find an open or short in the TPS, connectors and vehicle harness. If fault is indicated, disconnect TPS. Inspect connectors and terminals. If connectors and terminals are okay, replace TPS. Clear Continuous Memory Codes and repeat QUICK TEST. If no fault is indicated, go to next step.

95) Check EEC-IV Vehicle Harness While in KOEO Continuous Monitor Mode, shake, bend and wiggle small sections of EEC-IV harness from TPS sensor vehicle harness connector to firewall, and from firewall to ECA. If fault is indicated, isolate fault in wiring and repair as necessary. Clear Continuous Memory Codes and repeat QUICK TEST. If no fault is indicated, go to next step.

96) Check ECA & Harness Connectors Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect both connectors and terminals for damage. If connectors and terminals are damaged, repair as necessary. Clear Continuous Memory Codes and repeat QUICK TEST. If connectors and terminals are okay, fault cannot be duplicated at this time. Continuous Memory Code 63 testing is complete.