INTRODUCTION
Sensor operating range information can help determine if a sensor is out of calibration. An out-of-calibration sensor may not set a trouble code, but it may cause driveability problems.
SENSOR OPERATING SPECIFICATIONS
Note. Unless stated otherwise in testing procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
AIR TEMPERATURE SENSOR
Note. Air temperature sensor may be referred to as intake air temperature sensor.
Air temperature sensor is located in air intake, near air filter. Measure resistance between sensor terminals. For resistance specifications (Scheme 1)
Scheme 1
COOLANT TEMPERATURE SENSOR
Measure coolant temperature sensor resistance between sensor terminals. For resistance specifications see scheme 2
EGR GAS TEMPERATURE SENSOR
| Temperature °F (°C) | K/Ohms |
|---|---|
| 122 (50) | 69-89 |
| 212 (100) | 12-14 |
| 302 (150) | 3-4 |
| (1) For terminal identification and testing, see the I - SYS/COMP TESTS article in this section. | |
| (1) | For terminal identification and testing, see the I - SYS/COMP TESTS article in this section. |
EGR GAS TEMPERATURE SENSOR RESISTANCE (1)
MANIFOLD ABSOLUTE PRESSURE SENSOR
Note. See VACUUM SENSOR at end of article.
OXYGEN (O2) SENSOR
| Application | Specification |
|---|---|
| Tercel | 5.1-6.3 Ohms @ 68°F (20°C) |
| (1) Measure resistance between sensor terminals +B and HT. For terminal identification, see I - SYS/COMP TESTS article in this section. | |
| (1) | Measure resistance between sensor terminals +B and HT. For terminal identification, see I - SYS/COMP TESTS article in this section. |
O2 SENSOR HEATER RESISTANCE (1)
THROTTLE POSITION SENSOR (TPS)
| Clearance: In. (mm) (1) | Terminal (2) | Ohms |
|---|---|---|
| 0 (0) | VTA & E2 | 200-800 |
| .020 (.51) | IDL & E2 | 2300 Or Less |
| .028 (.71) | IDL & E2 | Infinite |
| Fully Open | VTA & E2 | 3300-10,000 |
| " | VC & E2 | 3000-7000 |
| (1) Clearance is between throttle lever and throttle stop screw. (2) For terminal identification and testing, see I - SYS/COMP TESTS article in this section. (3) Apply vacuum to throttle opener before checking TPS. | ||
| (1) | Clearance is between throttle lever and throttle stop screw. |
| (2) | For terminal identification and testing, see I - SYS/COMP TESTS article in this section. |
| (3) | Apply vacuum to throttle opener before checking TPS. |
THROTTLE POSITION SENSOR RESISTANCE (3)
VACUUM SENSOR
Note. Vacuum sensor may also be referred to as Manifold Absolute Pressure (MAP) sensor.
| Application | (1) Volts |
|---|---|
| Tercel | 4.00-6.00 |
| (1) If supply voltage is not within specification, check wiring circuit. | |
| (1) | If supply voltage is not within specification, check wiring circuit. |
VACUUM SENSOR SUPPLY VOLTAGE
| Applied Vacuum: In. Hg | Volts |
|---|---|
| 3.94 | .3-.5 |
| 7.87 | .7-.9 |
| 11.81 | 1.1-1.3 |
| 15.75 | 1.5-1.7 |
| 19.69 | 1.9-2.1 |
VACUUM SENSOR OUTPUT VOLTAGE DROP