Mazda B-Series 1997 Workshop Manual page 455

FT
ON-BOARD DIAGNOSIS SYSTEM
- -
Key ON, engine off.
Access DPFEGR PID.
Is DPFEGR PID voltage less than 0.05 volt?
STEP
-
10
No Go to step 13.
INSPECTION ACTION
-
Key OFF. Yes Remove jumper wire.
Leave DPFE sensor connector disconnected.
I Go to next step.
Connect jumper wire between DPFE SIG circuit and SIG
RTN circuit at sensor connector.
Measure resistance between DPFE SIG test pin 65 at
No Repair open in DPFE SIG circuit.
breakout box and DPFE SIG c~rcuit at DPFE sensor
Go to step 32.
connector.
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11
12
-
13
Is resistance less than 5.0 ohms?
- -
Yes Replace PCM.
Leave DPFE and PCM disconnected. Go to step 32.
Measure resistance between SIG RTN test pin 91 at
breakout box and SIG RTN circuit at DPFE sensor
No
Repair open in SIG RTN c~rcuit.
connector. Go to step 32.
Is resistance less than 5.0 ohms?
Yes Reconnect vacuum hoses.
-
Leave DPFE sensor connector disconnected. Yes Go to next step.
Key ON, engine off.
Measure voltage between VREF clrcuit and SIG RTN
I
circuit at DPFE sensor connector.
No Go to pinpoint test "VREF."
Is voltage between 4.0 and 6 0 volts?
Key OFF.
Leave DPFE sensor connector disconnected. : . . . . . . ' - . ' . e n s o r Go to step 32.
--
Install breakout box, leave PCM disconnected
Measure resistance between DPFE SIG test pin 65 and Repair short between DPFE SIG and VREF
VREF test pin 90 at breakout box.
I
c~rcult.
Is resistance greater than 10,000 ohms7
I
Go to step 32.
- -
I
Key OFF. Yes Go to next step
Leave DPFE sensor connector disconnected.
Install breakout box. leave PCM disconnected.
lnipect vacuum hoses for routing, pinching or plugging.
Are vacuum hoses OK?
Go to next step.
No Repair or replace vacuum hoses as
necessary.
- -
'
Go to step 32.
--
- -
- - - -
Yes Go to next step.
16
17
18
No Go to step 18.
-
- -
- -
- - ~
Key ON, engine off.
Access and note DPFEGR PID.
Disconnect EVR solenoid connector.
Start engine and run it at idle.
Compare DPFEGR PID at idle to engine off voltage.
Is DPFEGR PID voltage greater at idle by a minimum of
0.1 5 volt than with engine off, or is engine a no start or
stall?
- -
Key OFF.
Disconnect EVR solenoid vacuum hoses.
Remove EVR solenoid vent cap.
Remove filter and inspect for blockage or icing in case.
With EVR vacuum supply port plugged, apply 10 to 15
in-Hg of vacuum directly to EVR vacuum source port with
a hand vacuum pump.
- If vacuum holds or is slow to release to atmosphere,
EVR vent could be plugged or restricted.
Is EVR vent or filter plugged or restricted?
Key OFF.
Leave EVR solenoid connector disconnected.
I
Measure resistance across EVR solenoid.
1
Yes Repair or replace EVR solenoid.
I
Go
to
step 32.
Is resistance between 26 and 40 ohms?
'
No Replace EVR solenoid.
Go to step 32.
1
(
Yes Go to next step.
I
1
I
No Replace EVR solenoid.
Go to step 32.