2009 CHERY TIGGO fuel pressure

Downloaded from www.Manualslib.com manuals search engine Check reference values between ECM terminals and ground under the following conditions:
ECM TERMINAL NO.ITEMCONDITIONDATA (AVERAGE DC
VOLTAGE)
6 Injector 2
•Engine is running
• Warm-up condition
• Idle
• Accelerate suddenly Voltage: 11 - 14 V
7
Injector 3
27 Injector 1
47 Injector 4
ECM TERMINAL NO. ITEMCONDITIONDATA
17 Sensor (GND)
•Engine is running
• ECT: 78°C
• Idle: 795 RPM
• IAT: 36°C
• IAT signal: 1.88 V 0V
33 Regulated sensor supply 1 5 V
37 Air flow sensor 322 kg/h
1.39 V
On Board Diagnostic Logic
• Self-diagnosis detection logic.
DTC NUMBER DTC DEFINITION DTC DETECTION
CONDITION DTC SET
CONDITION POSSIBLE CAUSE
P0172 Fuel trim system too
rich Engine is running The amount of
mixture ratio
compensation is too
large (The mixture
ratio is too rich). •
MAF sensor
• Fuel injector
• Exhaust gas leaks
• Incorrect fuel
pressure
• Upstream O
2sensor
•ECM
DTC Confirmation Procedure:
Before performing the following procedure, confirm that battery voltage is more than 12 V.
• Turn ignition switch off.
• Connect the X-431 scan tool to the Data Link Connector (DLC) - use the most current software available.
• Turn ignition switch on.
• With the scan tool, record and erase stored DTCs in the ECM.
• Start engine and warm it to normal operating temperature, then select view DTC and data stream.
• If the DTC is detected, the DTC condition is current. Go to Diagnostic Procedure - Step 1.
• If the DTC is not detected, the DTC condition is intermittent (See Diagnostic Help and Intermittent DTC Trou-
bleshooting in Section 03 Electronic Engine Controls for more information.
NOTE :
While performing electrical diagnosis & testing, always refer to the electrical schematics for specific circuit
and component information.
DIAGNOSIS & TESTING
03
03–339Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine •Continuity should exist.
• Also check harness for short to power.
Is the check result normal?
Ye s>>Go to the next step.
No
>>Repair or replace the circuit for an open or short to power in harness or connectors.
5.CHECK FUEL PRESSURE
• Release fuel pressure to zero.
• Install fuel pressure gauge (2) and check fuel
pressure.
• Observe the following fuel pressures when testing (See Fuel Pressure Test in Section 04 Fuel Delivery)
FUEL PRESSURES
Key On 400 kPa (4 bar)
Key Off 380 kPa (3.8 bar) in 10 minutes
Engine Idle 400 kPa (4.0 bar) - 420 kPa (4.2 bar)
Is the check result normal?
Ye s>>Go to step 7.
No
>>Go to the next step.
DIAGNOSIS & TESTING
BESM030020
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03–341Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 6.DETECT MALFUNCTIONING PART
• Check the following:
Fuel pump and circuit
Fuel pressure regulator
Is the check result normal?
Ye s>>Go to the next step.
No
>>Repair or replace malfunctioning part.
7.CHECK MAF SENSOR
• Turn ignition switch off.
• Install all removed parts.
• Check air flow in data stream.
MAF SENSOR SIGNAL
TERMINAL NO. ITEMCONDITION DATA
37 Air flow sensor •
Engine is running
• ECT: 78°C
• Idle: 795 RPM
• IAT: 36°C
• IAT signal: 1.88 V 322 kg/h
1.39 V
Is the check result normal?
Ye s>>If with the X-431, go to the next step.
If without the X-431, go to step 9.
No
>>Check connectors for damaged or air flow signal circuit for short to power.
8.PERFORM ACTIVE TEST FUNCTION
• Start engine.
• Select ACTIVE TEST menu.
• Perform injector active test.
• Make sure that each test produces a momentary engine speed drop.
Is the check result normal?
Ye s>>Go to step 11.
No
>>Go to the next step.
9.CHECK FUNCTION OF INJECTOR
• Listen to each injector operating sound.
• Operating sound should exist.
Is the check result normal?
Ye s>>Go to step 11.
No
>>Go to the next step.
DIAGNOSIS & TESTING
03–342Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 10.CHECK INJECTOR CONTROL CIRCUIT
• Turn ignition switch off.
• Disconnect injector harness connector (1).
• Disconnect ECM harness connector.
• check harness for short to ground between following terminals.
• Continuity should not exist.
INJECTOR NO. ECM
TERMINAL INJECTOR
TERMINAL
12 72
262
372
44 72
Is the check result normal?
Ye s>>Go to the next step.
No
>>Repair or replace the circuit for short to ground in harness or connectors.
11 .CHECK INJECTOR RESISTANCE
• Disconnect injector harness connectors (See Fuel Pressure Test in Section 04 Fuel Delivery).
• Check the fuel injector resistance as shown in the following:
INJECTOR RESISTANCE
INJECTOR NO. INJECTOR
TERMINAL RESISTANCE
(APPROXIMATELY) (20°C)
1 1&2
11-16
2
1&2
3 1&2
4 1&2
DIAGNOSIS & TESTING
BESM040006
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03–343Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine ON-VEHICLE SERVICE
Engine Coolant Temperature (ECT) Sensor
Description
The Engine Coolant Temperature (ECT) sensor threads into the coolant outlet connector. The ECT is a negative
thermal coefficient sensor.
Operation
The ECT provides an input to the Engine Control Module (ECM). As temperature increases, resistance of the sensor
decreases. As coolant temperature varies, the ECT sensor resistance changes resulting in a different voltage value
at the ECT sensor signal circuit. The ECM uses the input to control air-fuel mixture, timing, A/C compressor and
radiator fan on/off times.
Removal & Installation
1. Disconnect the negative battery cable.
2. Drain the cooling system (See Cooling System Draining Procedure in Section 06 Cooling System).
WARNING!
Never remove the pressure relief cap under any conditions while the engine is operating or hot. Failure to follow
these instructions could result in personal injury or damage to the cooling system or engine. To avoid having
scalding hot coolant or steam blow out of the cooling system, use extreme care when removing the pressure
relief cap. Wait until the engine has cooled, then wrap a thick cloth around the pressure relief cap and turn it
slowly one turn (counterclockwise). Step back while the pressure is released from the cooling system. When you
are certain all the pressure has been released, (with a cloth) turn and remove the pressure relief cap. Failure to
follow these instructions may result in series personal injury.
3. Disconnect the coolant temperature sensor electri-cal connector.
CAUTION:
Remove the coolant temperature sensor when
the engine is cold.
4. Remove the engine coolant temperature sensor(1).
(Tighten: Engine coolant temperature sensor to 20
N·m)
5. Discard the O-ring.
LTSM030035
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03–427Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine Compression Gauge
Fuel Pressure Gauge
GENERAL INFORMATION
03–446Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine ECM Connector Pin-Out Table
ECM PIN-OUT TABLE
PINCIRCUIT IDENTIFICATION PINCIRCUIT IDENTIFICATION
1 Injector 1 39-
2 Injector 3 40-
3 -41A/C Pressure Switch
4 Idle Air Control 1 42-
5 Idle Air Control 3 43-
6 EGR Control 44-
7 Lan 1 45-
8 Fuel Pump Relay 46-
9 EVAP Control 47-
10 Ignition Coil 1 48Diagnostic Link K
11 -4 9 -
12 Switched Supply Voltage 50RPM
13 GND 51Lan 2
14 Injector 2 52Upstream Oxygen Sensor Heater
15 Injector 4 53-
16 -54Diagnostic Link K
17 Idle Air Control 2 55Ignition Switch Start
18 Idle Air Control 4 56Intake Air Temperature Sensor
19 Air Flow Sensor 57-
20 -58 -
21 Cooling Fan Control 59Downstream Oxygen Sensor
22 A/C Relay 60Upstream Oxygen Sensor
23 Ignition Coil 2 61-
24 -62Knock Sensor
25 Switched Supply Voltage 63-
26 GND 64Continuous Supply Voltage
27 -65Regulated Sensor Supply
28 -66Ignition Switch On
29 Generator G 67 Engine Coolant Temperature Sensor
30 -68Throttle Position Sensor
31 -69Atmosphere Pressure Sensor
32 MIL Lamp 70Speed In
33 Power Steering Switch 71Idle Position Switch
34 Main Relay 72Camshaft Position Sensor
35 -73Crankshaft Sensor
36 -74Air Flow Sensor
37 Generator FR 75P/N Switch
38 -76Sensor (GND)
GENERAL INFORMATION
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03–457Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine DIAGNOSIS & TESTING
Diagnostic Help
1. Confirm that the malfunction is current and carry-out the diagnostic tests and repair procedures.
2. If the Diagnostic Trouble Code (DTC) cannot be deleted, it is a current fault.
3. Use a digital multimeter to perform voltage readings on the Electronic Fuel Injection (EFI) system.
4. The scan tool connects to the Data Link Connector (DLC) and communicates with the ECM.
5. If the failure is intermittent perform the following:•Check for loose connectors.
• Look for any chafed, pierced, pinched, or partially broken wires.
• Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
• Look for the data to change or for the DTC to reset during the wiggle test.
• Look for broken, bent, pushed out or corroded terminals.
• Inspect the sensor and mounting area for any condition that would result in an incorrect signal, such as
damage or foreign material.
6. Remove the ECM from the troubled vehicle and install in a new vehicle and test. If the DTC can not be deleted, the ECM is malfunctioning. If the DTC can be deleted, return the ECM to the original vehicle.
Diagnostic Logic
If the DTC can not be deleted, it is a current failure.
If the DTC can be deleted, it is an intermittent incident. In many cases, the malfunction resolves itself (the part or
circuit function returns to normal without intervention). It is important to realize that the symptoms described in the
customer’s complaint often do not recur on (1st trip) DTC visits. Realize also that the most frequent causes of inter-
mittent incidents occurrences is poor electrical connections. Because of this, the conditions under which the incident
occurred may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may not
indicate the specific malfunctioning area.
Check if it is because of the loosening of cable joint.
Look for any chafed, pierced, pinched, or partially broken wires.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Look for broken, bent, pushed out or corroded terminals.
Inspect the sensor and mounting area for any condition that would result in an incorrect signal, such as damage,
foreign material.
Refer to any Technical Service Bulletins that may apply.
DIAGNOSTIC REFERENCE
•Check ground terminals for corroding or loose connection. Refer to Ground Inspection.
• Search for electrical incident. Refer to Diagnosis for an Electrical Incident.
• Check connector terminals. Refer to How to Check Terminal.
DURING ENGINE CHECKS AND REPAIRS USE CAUTION NOT TO HARM THE ENGINE MECHANICAL SYSTEM
• Check cylinder pressure.
• Check ignition timing.
• Check fuel system pressure.
• Check the EVAP system.
• Check for vacuum leaks.
• Check output of the TPS.
• Check the injectors for leaks.
Remove and install the doubtful ECM to a new vehicle and test it. If the DTC can not be deleted, the malfunction is
inside of ECM; if the DTC can be deleted, change the original ECM back and check it again according to above
items.
Inspect and clean all ECM, engine, and body grounds that are related to the DTC. If numerous trouble codes were
set, use a wire schematic and look for any common ground or supply circuits for any camshaft pulley DTCs inspect
for dirt/metal debris.
03–458Chery Automobile Co., Ltd.