Isuzu 2000 Trooper Workshop Manual page 1081

6E–212
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0155 – HO2S Heater Circuit Bank 2 Sensor 1 (Cont'd)
Step
5 Connect the test light between Bank 2 HO2S 1 ignition
feed and Bank 2 HO2S 1 heater ground.
Does the test light illuminate?
6 1. Allow the HO2S to cool for at least 15 minutes.
2. Using a DVM, measure resistance between the
Bank 2 HO2S 1 ignition feed and the Bank 2 HO2S 1
heater ground at the Bank 2 HO2S 1 pigtail.
Is the HO2S resistance within the specified values?
7 Repair the open Bank 2 HO2S 1 ignition feed circuit to
Bank 2 HO2S 1.
Is the action complete?
8 Repair the open Bank 2 HO2S 1 heater ground circuit.
Is the action complete?
9 1. Check for a poor connection at the Bank 2 HO2S 1
harness terminals.
2. If a poor connection is found, replace terminals.
Was a poor connection found?
10 Check for a poor Bank 2 HO2S 1 signal or low circuit
terminal connection at the Bank 2 HO2S 1 harness
connector and replace terminal(s) if necessary.
Did any terminals require replacement?
11 1. Ignition "OFF."
2. Disconnect the PCM and check the continuity of the
Bank 2 HO2S 1 signal circuit and the Bank 2 HO2S
1 low circuit.
3. If the Bank 2 HO2S 1 signal circuit or HO2S low
circuit measures over 5 ohms, repair open or poor
connection as necessary.
Was a problem found?
12 Check for a poor Bank 2 HO2S 1 low circuit terminal
connection at the PCM and replace the terminal if
necessary.
Did the terminal require replacement?
13 Check for a poor Bank 2 HO2S 1 signal circuit terminal
connection at the PCM and replace the terminal if
necessary.
Did the terminal require replacement?
14 Replace Bank 2 HO2S 1.
Is the action complete?
15 Locate and repair short to ground in Bank 2 HO2S 1
ignition feed circuit and replace the faulty fuse.
Is the action complete?
Action Value(s) Yes
— Go to Step 6
3-6 ohms Go to Step 9
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
— Verify repair
No
Go to Step 8
Go to Step 10
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—
Go to Step 10
Go to Step 11
Go to Step 12
Go to Step 13
Go to Step 14
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