Component Location
General Description

RPS(Rail Pressure Sensor), consists of piezzo electric element, measures rail pressure inside of common rail.

ECM determines optimum fuel injection quantity at specific engine condition based on RPS signal. RPS signal is also used as rail pressure regualtor feed back signal in order to achieve optimum rail pressure at certain engine condition.

DTC Description

P0193 is set when RPS output voltage is above the maximum value of 4830mV(4.8V) for more than 0.2 sec.. This code is due to the open or short in 1) RPS signal circuit 2) RPS ground circuit.

DTC Detecting Condition

Item

Detecting Condition

Possible Cause

DTC Strategy

●

Voltage monitoring

●

RPS circuit

●

RPS component

Enable Conditions

●

Engine running

Threshold Value

●

Output signal above the maximum value(above 4810mV)

Diagnostic Time

●

200ms

Fail Safe

Fuel cut

NO

●

Rail press. Sensor value fixed at 330bar

EGR Off

NO

Fuel Limit

YES

Check Lamp

YES

Specification
Diagnostic Circuit Diagram
Signal Waveform

Fig.1) This waveform shows the rise of RPS output voltage at rapid acceleration.

Monitor GDS Data
1.

Connect GDS to Data Link Connector (DLC).

2.

Warm engine up to normal operating temperature.

3.

Turn "OFF" electrical devices and A/C.

4.

Monitor "FUEL PRESSURE MEASURED", "RAIL PRESS. REGULATOR1", "INJ. PUMP REGULATOR" parameter on the GDS.

Specification :

Idle(without load)

Accelerating(stall test)

Diagnosis

INJ. PUMP REGULATOR

38 ± 5%

32 ± 5%

duty decreases

FUEL PRESSURE

MEASURED

28.5 ± 5 Mpa

145 ± 10 Mpa

press. increases

RAIL PRESS.

REGULATOR1

19 ± 5%

48 ± 5%

duty increases

Fig.1) Service data of Fuel pressure regulator valve at idle.

note

The waveform of rail pressure regulator valve installed at common rail shows 19% duty at idle,

duty rises to approx. 48% at acceleration to raise rail pressure. Duty rise means the increase of current.

→ If current rises, the returning quantity of fuel deliverd to common rail decreases and common rail pressure rises.

Terminal and Connector Inspection
1.

Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damge of component.

2.

Perform checking procedure as follows.

(1)

Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.

(2)

Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking device and connecting condition between terminal and wiring.

note

Disconnect the pin which requires checking at male connector and insert it to the terminal at female connector for checking connecting condition. ( after checking, reconnect the pin at correct position. )

3.

Is the problem found?

▶ Repair the trouble causing part and go to "Verification of Vehicle Repair".

▶ Go to "Power Circuit Inspection".

Power Circuit Inspection
1.

IG KEY "OFF", ENGINE "OFF".

2.

Disconnect RPS connector.

3.

IG KEY "ON".

4.

Measure the voltage between power terminal of RPS harness connector and chassis ground.

Specification : 4.8V~5.1V

5.

Is the measured voltage within the specification?

▶ Go to "Signal Circuit Inspection".

▶ Repair open in power circuit and go to "Verification of Vehicle Repair".

[ Check between power terminal of RPS harness connector and ECM harness connector. ]

Signal Circuit Inspection
1.

Check signal circuit voltage

(1)

IG KEY "OFF", ENGINE "OFF".

(2)

Disconnect RPS connector.

(3)

IG KEY "ON".

(4)

Measure the voltage between signal terminal of RPS harness connector and chassis ground.

Secification : 4.8V~5.1V

(5)

Is the measured voltage within the specification?

▶ Go to "Ground Circuit Inspection".

▶ Go to "2. Check open in signal circuit" as follows.

2.

Check open in signal circuit

(1)

IG KEY "OFF", ENGINE "OFF".

(2)

Disconnect RPS connector and ECM connector.

(3)

Check continuity between signal terminal of RPS harness connector and signal terminal of ECM harness connector.

Specification : continuity ( below 1.0Ω )

(4)

Is the measured resistance within the specification?

▶ Go to "3. Check short to battery in signal circuit" as follows.

▶ Repair open in RPS signal circuit and go to "Verification of Vehicle Repair".

[ Check the circuit between signal terminal of RPS harness connector and ECM harness connector. ]

3.

Check short to battery in signal circuit

(1)

IG KEY "OFF", ENGINE "OFF".

(2)

Disconnect RPS connector and ECM connector.

(3)

IG KEY "ON".

(4)

Measure the voltage between signal terminal of RPS harness connector and chassis ground.

Specification : 0.0V~0.1V

(5)

Is abnormal voltage measured in signal circuit(with both connectors disconnected)?

▶ Repair short to battery in signal circuit and go to "Verification of Vehicle Repair".

▶ Go to "Component Inspection".

Ground Circuit Inspection
1.

IG KEY "OFF", ENGINE "OFF".

2.

Disconnect RPS connector.

3.

IG KEY "ON".

4.

Measure the voltage between signal terminal of RPS harness connector and chassis ground. [ TEST "A" ]

5.

Measure the voltage between signal terminal and ground terminal of RPS harness connector. [ TEST "B" ]

( Signal terminal : Check + prove , Ground terminal : Check - prove )

Specification : [TEST "A"] Voltage - [TEST "B"] Voltage = below 200mV

6.

Is the measured voltage within the specification?

▶ Go to "Component Inspection".

▶ When "B" voltage is not detected : Repair open in ground circuit and go to "Verification of Vehicle Repair".

▶ When the voltage difference between "A" and "B" is above 200mV : Eliminate the causes of excessive resistance and go to "Verification of Vehicle Repair".

Component Inspection
1.

Visual Inspection of RPS

(1)

IG KEY "OFF", ENGINE "OFF".

(2)

Disconnect RPS connector.

(3)

Check if corrosion and damage in RPS terminal is detected.

(4)

Check RPS mounting torque and oil leakage.

(5)

Are the problems relevant to RPS found?

▶ Replace RPS if necessary and go to "Verification of Vehicle Repair".

▶ Go to "RPS waveform Inspection".

2.

RPS Waveform Inspection

(1)

IG KEY "OFF", ENGINE "OFF".

(2)

Connect RPS connector.

(3)

Connect an Oscilloscope to signal teminal of RPS connector.

(4)

After turning engine "ON", Check waveform at idle and during acceleration.

Specification : Refer to "Signal Waveform & Data" of "General Information".

(5)

Does RPS waveform look similar to standard "Signal Waveform & Data"?

▶ Go to "Verification of Vehicle Repair".

▶ Replace RPS and go to "Verification of Vehicle Repair".

Verification of Vehicle Repair

After a repair, it is essential to verify that the fault is corrected.

1.

After connecting GDS select "Diagnostic Trouble Codes(DTCs)" mode to and then clear DTC.

2.

Drive the vehicle within DTC Enable conditions in General information.

3.

After selecting "Diagnostic Trouble Codes(DTCs)" mode and check DTC is recorded again.

4.

Are any DTCs recorded ?

▶ Go to the DTC guide of recorded NO. in GDS.

▶ System operates within specification.

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