
The PCM provides ground
to one side of the coil in the fuel pump relay to control the fuel pump
relay. The other side of the fuel pump relay coil is connected to main
relay, which activates when the ignition switch is ON. The PCM monitors
the control circuit between the fuel pump relay and the PCM. When the
ignition switch is turned ON, the PCM energizes the fuel pump relay, which
sends power to the fuel pump.
Checking fuel pump relay
circuit continuously under detecting condition, if open or short in the
circuit is detected, PCM sets P0230.In addition, Take note that open
circuit in Main Relay may cause this P0230 code.
※ In addition, Take note
that open circuit in Main Relay may cause this P0230 code.
Item
|
Detecting
Condition
|
Possible Cause
|
DTC
Strategy
|
|
•
|
Open or short in fuel pump relay
circuit |
•
|
Open in Main Relay
circuit |
|
Enable
condition
|
•
|
11V ≤ Battery Voltage ≤
16V | |
threshold
value
|
|
diagnosis
time
|
|
MIL ON
condition
|
|

1. |
Check DTC Status
(1) |
Connect scantool to Data Link
Connector(DLC). |
(3) |
Select "DTC" button, and then Press "DTC
Status" to check DTC's information from the DTCs
menu. |
(4) |
Read "DTC Status"
parameter.

|
(5) |
Is parameter displayed "Present
fault"?

|
▶ Go
to "Terminal and connector inspection"
procedure.
|

|
▶
Fault is intermittent caused by poor contact in the
sensor's and/or PCM's connector or was repaired and PCM
memory was not cleared. Thoroughly check connectors for
looseness, poor connection, ending, corrosion,
contamination, deterioration, or damage. Repair or
replace as necessary and go to "Verification of Vehicle
Repair"
procedure.
|
| |
Terminal And Connector
Inspection |
1. |
Many malfunctions in the electrical system are
caused by poor harness and terminal condition. Faults can also be
caused by interference from other electrical systems, and mechanical
or chemical damage. |
2. |
Thoroughly check connectors for looseness,
poor connection, bending, corrosion, contamination, deterioration,
or damage. |
3. |
Has a problem been found?

|
▶ Repair or
replace if necessary and go to "Verification of Vehicle
Repair" procedure
|

|
▶ Go to
"Power Circuit Inspection"
procedure.
|
|
■ Check voltage
2. |
Disconnect fuel pump
relay. |
4. |
Measure voltage between battery power supply
terminals of fuel pump relay harness and chassis
ground.
Specification
: Approx. B+
| |
5. |
Is the measured voltage within specification
?

|
▶ Go to
"Control Circuit Inspection" procedure.
|

|
▶ Check
"Fuse" between fuel pump relay and main relay is not installed
or blown off. ▶ Check "Fuse"
between fuel pump relay and battery is not installed or blown
off. ▶ Check the Main relay that is
not installed or blown off. ▶
Repair or replace as necessary and then, go to "Verification
of Vehicle Repair"
procedure.
|
|
Control Circuit
Inspection |
■ Check Voltage
2. |
Disconnect fuel pump
relay. |
4. |
Measure voltage between fuel pump relay
control terminal of Fuel pump relay harness and chassis
ground.
Specification
: Approx. 2.5V
| |
5. |
Is the measured voltage within specification
?

|
▶ Go to
"Component Inspection" procedure.
|

|
▶ Repair or
repalce as necessary and then, go to "Verification of Vehicle
Repair"
procedure.
|
|
■ CHECK FUEL PUMP RELAY
2. |
Disconnect Fuel Pump
Relay. |
3. |
Measure resistance between battery power
supply and power supply to fuel pump motor terminals of fuel pump
relay. (Measurement "A") |
4. |
Measure resistance between battery power
supply and fuel pump relay control terminals of fuel pump
relay.(Measurement "B")
Specification :
Terminal
|
Cntinuity
|
Battery power supply - Power supply to Fuel pump
motor
|
NO
|
Battery power supply - Fuel pump relay
control
|
YES (Approx. 70Ω ~
120Ω)
|
|
5. |
Is the measured resistance within
specification ?

|
▶
Substitute with a known - good PCM and check for proper
operation. If the problem is corrected, replace PCM and go to
"Verification of Vehicle Repair" procedure.
There is a memory reset function
on scantool that can erase optional parts automatically
detected and memorized by PCM. After testing PCM on the
vehicle, use this function before reusing the
PCM | |

|
▶
Substitute with a known - good Fuel Pump Relay and check for
proper operation.If the problem is corrected, replace Fuel
Pump Relay and go to "Verification of Vehicle Repair"
procedure.
|
|
Verification Of Vehicle
Repair |
After a repair, it is
essential to verify that the fault has been corrected.
1. |
Connect scantool and select "DTC"
button. |
2. |
Press "DTC Status" button and confirm that
"DTC Readiness Flag" indicates "Completed". If not, drive the
vehicle within conditions noted in the freeze frame data or enable
conditions |
3. |
Read "DTC Status"
parameter |
4. |
Is parameter displayed "History(Not Present)
fault"?

|
▶ System
performing to specification at this time. Clear the
DTC
|

|
▶ Go to the
applicable troubleshooting
procedure.
|
|