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Home >> Geo >> 1995 >> Metro Base, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 1.3L 4-CYL >> Self-Diagnostic System >> DTC Definitions
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DTC Definitions

NOTE: DTCs will be recorded at various operating times. Some DTCs require sensor or switch operation for 5 seconds and others may require longer under certain conditions. Some DTCs may not set in a service bay operational mode.
DTC IDENTIFICATION

DTC Circuit Affected Probable Cause
12 ECM Diagnostic System (1)
13 HO2S Signal Voltage Does Not Change
14 ECT Sensor High Voltage In-Low Temp. Indicated
15 ECT Sensor Low Voltage In-High Temp. Indicated
21 TP Sensor High Voltage Input
22 TP Sensor Low Voltage Input
23 IAT Sensor High Voltage In-Low Temperature Indicated
24 VSS Constant Signal
25 IAT Sensor Low Voltage In-High Temperature Indicated
31 MAP Sensor Low Voltage In-Low Vacuum
32 MAP Sensor High Voltage In-High Vacuum
41 Ignition Signal No Signal
42 CMP Sensor No Signal For 2 Seconds
46 ISC Motor Incorrect ISC Motor Signal
51 EGR System Closed Loop Or Incorrect EGR Signal
(1) DTC 12 indicates ECM diagnostic system is operating. If DTC 12 does not display or MIL does not light, see appropriate ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK chart under DIAGNOSTIC DTC CHARTS.