Mazda 2002 6 Workshop Manual page 362

Fuel Pump Operation Inspection
1. Connect WDS or equivalent to the DLC-2.
2. Remove the fuel-filler cap.
3. Turn the ignition switch to ON position.
4. Turn the fuel pump relay from off to on using the FP PID and inspect if the operation sound is heard.
• If no operation sounds is heard, proceed to next step.
5. Measure the voltage at harness side fuel pump connector terminal B.
Specification
B+ (Ignition switch is on)
• If the voltage is as specified, inspect the following.
— Fuel pump continuity
— Fuel pump GND
— Wiring harness between fuel pump relay and PCM terminal 4P (without immobilizer system), 4Q (with
immobilizer system)
• If not as specified, inspect the following.
— Fuel pump relay (See
— Wiring harness and connector (Main relay-fuel pump relay-fuel pump)
Fuel Pump Control System Inspection
1. Connect WDS or equivalent to the DLC-2.
2. Turn the ignition switch to ON position.
3. Select FP PID.
4. Turn the fuel pump relay from off to on and inspect if the operation sound of the fuel pump relay is heard.
• If no operation sound is heard, inspect the fuel pump relay.
• If the fuel pump relay is normal, inspect the following.
— Wiring harnesses and connectors (Main relay-fuel pump relay-PCM)
Spark Test
1. Remove the fuel pump relay.
2. Verify that each high-tension lead and connector is connected properly.
3. Inspect the ignition system in the following procedure.
Warning
• High voltage in the ignition system can cause strong electrical shock which can result in serious
injury. Avoid direct contact to the vehicle body during the following spark test.
STEP
1 Note
• No.1 and No.4 cylinders and No.2 and
No.3 cylinders are ignited simultaneously.
Disconnect high-tension lead from spark plugs.
Remove spark plugs.
Reconnect spark plugs to high-tension lead.
Ground spark plugs to engine.
Is strong blue spark visible at each cylinder while
cranking?
2 Inspect spark plugs for damage, wear, carbon
deposits and proper plug gap.
Are spark plugs okay?
3 Inspect high-tension leads for insulation
damage, looseness, shorting or other damage.
Are high-tension leads okay?
4 Inspect following wiring harnesses for open or
short:
• Ignition coil terminal C-PCM terminal 1A
• Ignition coil terminal A-PCM terminal 1B
Are wiring harnesses okay?
5 Measure voltage at terminal B in ignition coil.
Is voltage reading B+?
6 Does PCM connector or ignition coil connector
have poor connection?
F–232
TROUBLESHOOTING
T–24 RELAY
INSPECTION
INSPECTION.)
RESULTS
Yes Ignition system is okay.
No Some cylinders do not spark:
Go to next step.
All cylinders do not spark:
Go to Step 5.
Yes Go to next step.
No Replace spark plugs, then go to Step 1.
Yes Go to next step.
No Replace high-tension leads, then go to Step 1.
Yes Inspect and replace ignition coil.
See G–9 IGNITION COIL
No Repair or replace malfunctioning parts, then go to Step
1.
Yes Go to next step.
No Inspect power supply circuit of ignition coil.
Yes Repair or replace connector, then go to Step 1.
No Go to next step.
ACTION
INSPECTION.