Connect A 3-Amp Fused Jumper Wire Between The Signal Circuit And The Low Reference Circuit; 4.8 Volts; Is The Iat Sensor Parameter Less Than The Specified Value? Go To Step; Go To Step 6 - Isuzu 2008MY N Series Workshop Manual

1A-126 Engine Control System (4HK1)
Step
Observe the Fuel Temperature (FT) Sensor
parameter with a scan tool.
3
Is the FT Sensor parameter more than the
specified value?
1. Turn OFF the ignition.
2. Disconnect the FT sensor harness connector.
3. Connect a DMM between the signal circuit
(pin 2 of E-22) and a known good ground.
4
4. Turn ON the ignition, with the engine OFF.
Is the DMM voltage more than the specified
value?
Important: The FT sensor may be damaged if the
sensor signal circuit is shorted to a voltage source.
1. Test the signal circuit between the ECM (pin
83 of E-12) and the FT sensor (pin 2 of E-22)
5
for a short to battery or ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?

Connect a 3-amp fused jumper wire between the

signal circuit and the low reference circuit (pins 1
and 2 of E-22).
6
Is the FT Sensor parameter less than the
specified value?
Connect a 3-amp fused jumper wire between the
signal circuit of the sensor harness (pin 2 of E-22)
and a known good ground.
7
Is the FT Sensor parameter less than the
specified value?
1. Test the signal circuit between the ECM (pin
83 of E-12) and the FT sensor (pin 2 of E-22)
for an open circuit or high resistance.
8
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Notice: The FT sensor shares the low reference
circuit with other sensors. A fault condition in the
low reference circuit may set DTCs on sensors that
share this circuit.
1. Test the low reference circuit between the
9
ECM (pin 109 of E-12) and the FT sensor (pin
1 of E-22) for an open circuit or high
resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
1. Test the signal circuit between the ECM (pin
83 of E-12) and the FT sensor (pin 2 of E-22)
for a short to any 5 volts reference circuit.
10
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Action Value(s) Yes

4.8 volts

Go to Step 4
5.5 volts
Go to Step 5
—
Go to Step 15
0.1 volts
Go to Step 10
0.1 volts
Go to Step 9
—
Go to Step 15
—
Go to Step 15
—
Go to Step 15
No
Go to Diagnostic
Aids

Go to Step 6

Go to Step 14
Go to Step 7
Go to Step 8
Go to Step 12
Go to Step 12
Go to Step 11