Mazda B-Series 1997 Workshop Manual page 459

ON-BOARD DIAGNOSIS SYSTEM
STEP
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INSPECTION ACTION
Key OFF. Yes Go to next step.
Leave EVR solenold disconnected.
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Measure resistance across EVR solenold. No Replace EVR solenold.
Is res~stance between 26 and 40 ohms?
)
Go to step 15.
Key OFF. Yes Repair short to PWR circuit.
Disconnect EVR solenoid connector.
1
Go to step 15.
Install breakout box, leave PCM disconnected.
Key ON, engine off.
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Measure voltage between EVR test pin 47 at breakout box
NO
G , to next step,
and chassis around.
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Is voltage gr&ter than 1.0 volts?
1
l1
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Key OFF.
Leave EVR solenoid and PCM disconnected.
Yes Go to next step
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Measure resistance between EVR test pin 47 at breakout
N ,
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R~~~~~ open in EVR circuit,
box and EVR circuit at solenoid connector.
Go to step 15.
Is resistance less than 5.0 ohms?
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Key OFF. Yes Replace PCM.
Reconnect PCM and EVR solenoid connectors.
1
Go to step 15.
Disconnect vacuum hose at EGR valve and connect to
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vacuum gauge.
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Key 0 ~ , > n $ n e running. No
1
Replace EVR solenoid.
Jumper EVR test pin 47 at breakout box to chass~s ground
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GO
to step 15.
while enaine is at idle.
Is vacuuh gauge reading 4.0 in-Hg or greater?
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13
14
Key OFF.
Disconnect vacuum hoses at EGR valve and plug hoses.
Connect vacuum pump to EGR valve.
Start engine and run it at idle.
Access DPFEGR PID and RPM PID.
Slowly apply 5-10 in-Hg of vacuum to EGR valve and hold
it for 10 seconds. If engine wants to stall, increase rpm
with throttle to maintain a minimum of 800 rpm.
Look for the following:
-
EGR valve starts opening at about 1.6 in-Hg
vacuum, indicated by increasing DPFEGR PID.
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DPFEGR PID increasing until EGR valve i s fully
open. DPFEGR PID should read 2.5 volts minimum
with full vacuum applied.
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DPFEGR PID steady when vacuum is held. If
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voltage drops within a few seconds, EGR valve or
vacuum source could be leaking.
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Does DPFEGR PID indicate that EGR valve is functioning
as described in this test?
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Key OFF. Yes Isolate fault and repair or replace as
Install breakout box to PCM and vehicle harness
necessary.
connector. Go to next step.
Disconnect vacuum hose at EGR valve and connect to
vacuum gauge.
Key ON, engine running.
Jumper EVR test pin 47 at breakout box to chassis ground
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-
.
- - -
- -
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while engine is at idle.
Observe vacuum gauge whil
me. Go to "Intermittent Concerns."
- Lightly tap on EVR solenoi page FT-69
connector, vacuum lines and vehicle harness.
- Fault is indicated by a sudden drop in vacuum reading.
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Is fault indicated?
p a -
15 Perform After Repair Procedure to ensure customer's concern has been resolved.