11

26. Attach the extension harness positive ring terminal to the battery positive (+) post
and torque to 15 N•m or (11 lb•ft). Apply three (3) tie straps to secure the extension
harness wiring to the battery positive cable as shown in Figure 26. The extension
harness positive side contains an inline fuse.

Inline Fuse
Figure 26 - Tie strap location
27. Attach the extension harness negative ring terminal to battery front frame ground
P-5. (See Figure 27.)
CAUTION: Do not connect the negative (-) side terminal of the wire harness to the
battery at this time.

Figure 27 - P-5 ground

12

28. Route extension harness along the front frame harness and to the H-101 connector
as shown in Figure 28. Apply tie straps loosely to hold harness in place. Disconnect
the H-101 connector. On the front frame, harness side of the H-101 connector
remove the electrical tape insulation and expose the red/black wire at pin 31. (See
Figure 29.)

Pin 31

Figure 28 – H-101 connector shown by red Figure 29 - Red/black wire leading to pin
31
circle
29. Using wire strippers, remove 15mm of insulation from the red/black wire 30mm to
45mm from the back of the H-101 connector on the front chassis harness. (See
Figure 30.)
30. Use wire strippers to remove 15mm of insulation from the end of the red/black wire
on the extension harness. (See Figure 30.)
IMPORTANT: Do not cut wire in half in the main front frame harness while
removing insulation.
31. Use a soldering iron to solder the two wires together.
32. Use supplied mastic tape to wrap and insulate the exposed wiring, then cover with
vinyl electrical tape as shown in Figure 31.

13

Figure 30

Figure 31

33. Re-secure the wiring into the wire loom protective cover. (See Figure 32.)
 Use vinyl electrical tape to wrap the harness where the ends of the wiring
loom protective cover contact the electrical harness.
 Secure the wires into the loom ensuring that all exposed wiring is covered.
 Wrap the wiring loom protective cover with vinyl electrical tape.
34. On shorter wheel base trucks, extra extension harness will have to be bundled and
secured. Apply tie straps to secure the wire bundle to the front frame harness as
shown in Figure 33.

Figure 32

Figure 33

35. Reconnect the H-101 connector by fully seating the connector and placing the cam
lock in the locked position. (See Figures 34 and 35.)

14

CORRECT

INCORRECT

Figure 34

Figure 35

CAUTION: Water intrusion may occur if the connector is not fully seated, resulting
in electrical damage.
36. Tighten the tie straps that were installed loosely in Step 25 along length of new
extension harness.
37. Is the vehicle equipped with screw on clear bowl shown in Figure 36?


Yes, perform Step 38 to Step 46 for installation of the CLEAR BOWL
TO SEDIMENTER TO METAL KIT (Part number is listed under
“Parts Information” at the beginning of this bulletin).



No, skip to Step 47.

15

Figure 36
REMOVAL OF CLEAR BOWL ASSEMBLY
Note: Be sure to place a drain tray on the ground underneath the sedimenter/prefilter assembly area.
38. Disconnect the sedimenter sensor. (See Figure 37, #1.)
39. Drain fuel in sedimenter. (See Figure 37, #2.)
40. On 2014 MY vehicles disconnect the DEF hose by removing the clip from DEF line
and set aside to reuse. (See Figure 37, #3.)
41. Loosen the clamp and disconnect the fuel supply line at the filter housing. Save
this supply line to reuse. (See Figure 37, #4.)
42. Loosen clamps and disconnect the fuel sedimenter from the supply pump fuel hose
at the sedimenter. (See Figure 37, #5.)
43. Loosen and remove bolts from mounting bracket and remove the fuel sedimenter
assembly along with old bracket. (See Figure 37, #6.)

16

3
5

6

4

2
1

Figure 37 – Old Filter Assembly Removal

INSTALLATION
44. Mount the new filter bracket onto the vehicle chassis bracket and torque to 41.4
Nm (37 lb ft). (See Figure 38.)

Figure 38 – Fuel filter bracket

17

45. Remove and discard the old fuel pump supply hose and clamps. Drain fuel as
necessary. Attach the new fuel pump supply hose to the fuel supply line and clip
into place with the new hose clamps.
46. Secure the wiring harness with the new band clips/zip ties tucked against the
sedimenter-mounting bracket. (See Figure 39.) Continue to Step 51.

Figure 39 – Tie strap locations
REMOVAL OF ORIGINAL FUEL SEDIMENTER ASSEMBLY
47. Place a drain tray on the ground underneath the sedimenter/pre-filter assembly
area. Drain fuel from sedimenter into the drain pan.
48. Disconnect the water sensor connector.
49. Loosen and move the fuel clamps and then remove the fuel inlet hose and fuel
outlet hose at the filter sedimenter housing.
50. Remove the two (2) 12mm mounting bolts holding the fuel sedimenter to its
mounting bracket. (See Figure 40.) Set bolts aside to use during re-assembly.

18

Figure 40

INSTALLATION OF NEW HEATED FUEL SEDIMENTER ASSEMBLY
51. Inspect Heated Fuel Filter Kit for inventory. (See Figure 41.)

Figure 41
Kit Contents
 Filter assembly with element
 Fuel sedimenter
 Banjo bolt (1) with gaskets (2)
 Spring clips (4)
 Band clip (1)
 Mastic tape (1)
 Tie straps (30)
 Extension harness kit (1) not pictured
 Relay: ISO; Micro (1) not pictured
 Relay: MR8 (1) not pictured (11-15MY only)

52. Mount the Heated Fuel Filter Sedimenter using the mounting bolts set aside during
removal. Torque to 25Nm (18 lb•ft).
53. Reconnect the fuel inlet hose and outlet hose at the Sedimenter. Reposition hose
clamps back onto the pipes. (See Figure 42.) For 2014MY reconnect the DEF hose
and reposition hose clamps back into place.

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Figure 42
NOTE: ENSURE NO TWISTS ARE PRESENT IN THE FUEL HOSES.
54. Connect the water sensor and heated sedimenter connectors. (See Figure 43.)
Heated Sedimenter Connector

Water Sensor
Figure 43 – Connector locations
55. Replace banjo bolt at fuel supply pump with new banjo bolt and two new gaskets
and torque to 17 N•m (12.5 lb•ft). (See Figures 44 and 45.)

20

Gaskets

Banjo Bolt

Figure 44

Figure 45

56. Replace main fuel filter element. (See Figure 46.)
CAUTION: Use a catch pan to prevent any spillage of diesel fuel.

Figure 46
57. Reconnect the negative (-) battery cable to the battery post. Torque to 15 N•m (11
lb•ft).
21

58. Bleed fuel system per the instructions in the applicable Isuzu WSM.
TEST HEATER CIRCUIT OPERATION
59. Start the engine.
60. Disconnect the heated fuel sedimenter electrical connector located at the top of
the fuel sedimenter and using a voltmeter verify that there is 12V to 14V present.
(See Figure 43 at Step 54.)


If there is no voltage or voltage is low, turn the engine control switch to the
“OFF” position. Check for an Open circuit or Short circuit in the extension
harness and perform repairs as necessary. When repairs are complete
return to Step 59.



If 12V to 14V output is present, reconnect the electrical connector. Turn off
engine and continue to Step 61.

61. Installation is complete.

22

FUEL HEATER WIRING SCHEMATIC
16MY-17MY

11MY-15MY

23

HARNESS TERMINAL/FUSE BOX LOCATION ASSIGNMENTS
Component
description

Harness
description

Fuse box
location

Comment
Small terminal, engine harness
Small terminal, fuel heater relay
Small terminal, jumper wire
Large terminal, front frame
harness
Small terminal, to 15 Amp fuse
Small terminal, ground
Large terminal, fuel heater relay
Large terminal, run relay
Eyelet, battery bus
Fuse Terminal
Fuse Terminal
Black Connector
Eyelet
Splice
Splice

Run Relay 1
Run Relay 1
Run Relay 1
Run Relay 1

White/ Blue
Blue/ White
Red/Black
Red/Black

T1
T2
T3
T4

Heater Relay 2
Heater Relay 2
Heater Relay 2
Heater Relay 2
Heater Power
Heater Fuse
Heater Fuse
Heater Connector
Ground
Run Relay Power
Run Relay Signal

Blue/White
Black
Black/Red
White
White
White
White
2 wire
Black
Black/Red
Blue/White

T5
T6
T7
T8
B1
F1
F1
C1
G1
S1
S2

24

GROUND

RUN RELAY

FRONT FRAME HARNESS
/FUEL HEATER
FUSE/POWER

POWER:
KEY ON/IGN

HEATER RELAY

11MY-17MY Harness Connection by Location
Items outlined in red are only on 11-15MY vehicle harness.
WARRANTY INFORMATION
The above noted condition is not a defect from manufacturing. The cost to add this
secondary fuel filter kit to an Isuzu vehicle is not eligible for reimbursement under any
Isuzu warranty.
25