DTC P0183 Without RPO CTF
Circuit Description
The fuel temperature sensor (FTS) is a thermistor. The engine control module (ECM) supplies the FTS a reference voltage of 5 volts on the signal circuit and also provides a ground circuit to the sensor. When the FTS is cold, the resistance is high. The FTS signal voltage remains near the supplied voltage cold and decreases the signal voltage as the sensor warms. The control module monitors the FTS signal circuit in order to calculate the temperature of the fuel entering the engine. If the ECM detects an excessively high FTS voltage, a low temperature indication, this DTC will set.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The FTS temperature is less than -50°C (-58°F) for 2 seconds.
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | If a short to a separate 5-volt source occurs, this diagnostic trouble code (DTC) may set. If this is the problem, a continuity test to all other ECM circuits will be necessary in order to diagnose the specific circuit. |
| • | Before starting a cold engine, the FTS should be within a few degrees of the manifold air temperature (MAT) reading |
| • | Use the Temperature vs. Resistance table in order to test the FTS at various temperature levels and in order to evaluate the possibility of a skewed sensor. |
| • | If the condition is suspected of being intermittent, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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If DTC P0183 can only be repeated by duplicating the Failure Records, refer to the Temperature vs Resistance table. The table may be used to test the FTS at various temperatures to evaluate the possibility of a shifted sensor that may be shorted above or below a certain temperature. If this is the case, replace the FTS. If the FTS appears to be OK, the malfunction is intermittent. Refer to Diagnostic Aids.
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Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.
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The ECM in this vehicle uses an electrically erasable programmable read-only memory (EEPROM). If the PCM is replaced, the new ECM must be programmed.
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||
2 |
Does the FTS temperature measure less than the specified value? | -50°C (-58°F) | Go to Step 4 | Go to Step 3 | ||||||
Does the DTC reset? | -- | Go to Step 4 | Go to Diagnostic Aids | |||||||
Does the FTS temperature measure more than the specified value? | 138°C (280°F) | Go to Step 8 | Go to Step 5 | |||||||
5 |
Does the FTS measure more than the specified value? | 138°C (280°F) | Go to Step 7 | Go to Step 6 | ||||||
6 |
Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 | ||||||
7 |
Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 | ||||||
8 |
Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 | ||||||
9 |
Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 | ||||||
Replace the FTS. Refer to Fuel Temperature Sensor Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- | |||||||
11 | Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data . Did you complete the replacement? | -- | Go to Step 12 | -- | ||||||
12 |
Does the DTC run and pass? | -- | Go to Step 13 | Go to Step 2 | ||||||
13 | With the scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||
DTC P0183 With RPO CTF
Circuit Description
The fuel temperature sensor is a variable resistor. The fuel temperature sensor has a signal circuit and a low reference circuit. The fuel temperature sensor measures the fuel temperature of the fuel. The engine control module (ECM) supplies 5 volts to the fuel temperature signal circuit and a ground for the fuel temperature low reference circuit. When the fuel temperature sensor is cold, the sensor resistance is high. When the air temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the fuel temperature signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the fuel temperature signal circuit. If the ECM detects an excessively high fuel temperature signal voltage indicating a low temperature, this DTC will set.
Conditions for Running the DTC
| • | The ignition switch is ON. |
| • | The battery voltage is between 10-16 volts. |
Conditions for Setting the DTC
The ECM detects that the fuel temperature signal voltage is more than 4.8 volts.
Action Taken When the DTC Sets
| • | The ECM illuminates the malfunction indicator lamp (MIL) and Reduced Engine Power indicator lamp, if fitted, when the diagnostic runs and fails. |
| • | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
| • | The ECM uses fuel temperature -29°C (-20.2°F) condition for starting the engine. |
| • | The ECM uses fuel temperature 90°C (194°F) condition for the engine running. |
| • | The ECM limits the fuel injection quantity for fail-safe operation. |
| • | The ECM closes the exhaust gas recirculation (EGR) valve and holds the EGR valve to a closed position. |
| • | The ECM inhibits cruise control. |
Condition for Clearing the DTC
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | Before starting a cold engine, the fuel temperature sensor and the intake air temperature (IAT) sensor temperature should be relatively close to each other. |
| • | Use the Temperature vs. Resistance table to test the fuel temperature sensor at various temperature levels to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns. Refer to Temperature Versus Resistance . |
| • | If an intermittent condition is suspected, the following may cause an intermittent: |
| - | Poor connections |
| - | A misrouted harness |
| - | Rubbed through wire insulation |
| - | Broken wire inside the insulation |
| • | Inspect for the following conditions: |
| - | Poor connection at ECM--Inspect the harness connectors for the following conditions: |
| • | Backed-out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal to wire connection |
| - | Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the Engine Coolant Temperature display on the scan tool while moving the connectors and the wiring harness related to the sensor. A change in the display will indicate the location of the fault. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |||||
2 |
Did the DTC fail this ignition? | -- | Go to Step 3 | Go to Diagnostic Aids | ||||
3 |
Is the DMM voltage more than the specified range? | 4.5-5.5 V | Go to Step 4 | Go to Step 5 | ||||
4 |
Important: The fuel temperature sensor may be damaged if the circuit is shorted to a voltage source.
Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | ||||
Is the Fuel Temperature Sensor parameter more than the specified value? | 135°C (275°F) | Go to Step 9 | Go to Step 6 | |||||
6 |
Is the Fuel Temperature Sensor parameter more than the specified value? | -44.7°C (-48.4°F) | Go to Step 8 | Go to Step 7 | ||||
7 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 | ||||
8 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 | ||||
9 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 | ||||
10 |
Important: The fuel temperature sensor may be damaged if the circuit is shorted to a voltage source.
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 | ||||
11 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 | ||||
12 | Replace the fuel temperature sensor. Refer to Fuel Injection Pump Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||
13 |
Important: The new ECM must be programmed. Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||
14 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 15 | ||||
15 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK | ||||||
