Chery A11. Manual — part 182

Maintenance Manual for Chery · Windcloud

M7.9.7 EFI System

Failure code: P0646 too low control circuit voltage of air conditioner

compressor relay

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “OFF”.

Go to next step

Yes

Go to Step 4

2

Unplug air conditioner compressor relay, turn
ignition switch to “ON”, check voltages between
Pin 30, 85 of relay (power supply terminals of
relay) and cathode of power supply to see if they are
around 12V.

No

Go to next step

Yes

Repair or
replace wire
harness

3

Check power supply terminal circuit of relay to see
if open circuit or short circuit to ground occurs.

No

Go to Step 2

Yes Replace

relay

4

Check the voltage between Pin 86 of relay (control
terminal of air conditioner compressor relay) and
cathode of power supply to see if it is around 3.7V.

No

Go to next step

Yes

Repair or
replace wire
harness

5

Check the connection between Pin 86 of relay
(control terminal of air conditioner compressor
relay) and Pin 70 of ECU to see if short circuit to
ground occurs.

No

Diagnosis
Instruction

Failure code: P0647 too high control circuit voltage of air conditioner

compressor relay

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “OFF”.

Go to next step

Yes

Go to Step 4

2

Unplug air conditioner compressor relay, turn
ignition switch to “ON”, check voltages between
Pin 30, 85 of relay and cathode of power supply to
see if they are around 12V.

No

Go to next step

Yes

Repair or
replace wire
harness

3

Check power supply terminal circuit of relay to see
if open circuit or short circuit to ground occurs.

No

Go to Step 2

Yes Replace

relay

4

Check the voltage between Pin 86 of relay (control
terminal of air conditioner compressor relay) and
cathode of power supply to see if it is around 3.7V.

No

Go to next step

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Maintenance Manual for Chery · Windcloud

M7.9.7 EFI System

Step Operation

Result Solution

Yes

Repair or
replace wire
harness

5

Check the connection between Pin 86 of relay
(control terminal of air conditioner compressor
relay) and Pin 70 of ECU to see if short circuit
occurs.

No

Diagnosis
Instruction

Failure code: P1651 control circuit error of fault indicating lamp

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Go to next step

2

Test operation of engine fault indicating lamp using
“Actuator Operation Test” function of scanner,
observe if it keeps off or on.

No System

normal

Yes

Repair or
replace wire
harness

3

Check fault indicating lamp power supply terminal
circuit of engine to see if open circuit or short
circuit to ground occurs.

No

Go to next step

Yes

Repair or
replace wire
harness

4

Check the connection between the pin at control
terminal of engine fault indicating lamp and Pin 29
of ECU to see if open, short circuit to power/ground
occurs.

No

Diagnosis
Instruction

37

Maintenance Manual for Chery · Windcloud

M7.9.7 EFI System

6. Diagnostic Steps for Various Engine Failures

Preliminary inspection shall be carried out before proceeding with diagnostic steps for
any engine failure:
(1). Make sure ECU and fault indicating lamp are working normally (models without fault

indicating lamp directly go to next step).

(2). Check with scanner or flash lamp to make sure that there is no failure information

recorded.

(3). Check warming-up idling data of ECU with scanner to make sure that each value is

within normal range.

(4). Confirm the existence of failure complained by vehicle owner and locate the specific
failure.
Then appearance inspection:
 Check ground point of wire harness to see if it is clean and firm.
 Check vacuum pipe to see if it is properly connected, or if it is broken or twisted.
 Check pipelines to see if blockage occurs.
 Check intake pipe to see if it is squashed or damaged.
 Check the sealing surface between throttle body and intake manifold to see if it is in good

condition.

 Check high voltage wire of ignition system to see if it is properly laid out with no breakage

or aging.

 Check connections to see if they are properly made; check contacts to see if they are loosed

or poorly connected.

38

Maintenance Manual for Chery · Windcloud

M7.9.7 EFI System

1). Engine dose not rotate or rotates slowly when starting

Step Operation

Result

Solution

Yes

Go to next step

1

Check the voltage between two terminals of
accumulator with a multimeter to see if it is around
10-12.5V.

No

Repair or replace
accumulator

Yes

Go to next step

2

Turn ignition switch to “ON”. Check the voltage on
terminal of ignition switch connected to anode of
accumulator with a multimeter to see if it is around
10-12.5V.

No

Repair terminal
or change wire

Yes

Go to next step

3

Keep iginition switch at “ON”, check the voltage on
terminal to ignition switch connected to starting
motor push-pull coil with a multimeter to see if it is
higher than 8V.

No

Repair or replace
ignition switch

Yes

Repair or replace
starting motor

4

Check starting motor with a multimeter to see if open
or short circuit occurs.

No

Go to next step

Yes

Eliminate failure

5

Check engine to see if it is stuck due to poor
lubrication.

No

Go to next step

Yes

Replace lubricant
or oil with proper
models

6

In case of cold weather, check engine lubricant and
gearbox oil to see if they cause excessive resistance to
starting motor.

No

Check other parts

39