TK 55676-19-IM-EN
79
Priming the Heater Fuel Pump (Heat Option)
IIm
mp
po
orrtta
an
ntt:: It is important the heater fuel pump be primed before attempting to operate the heater for the first time.
Failure to prime the pump will cause the unit to shutdown, set diagnostic codes and cause damage to the
fuel pump.
Special Tools Required
Heater Priming Harness (204-1144)
N
No
otte
e:: Verify there is a sufficient amount of fuel in the fuel tank before beginning the priming procedures.
The heater uses a pulse style fuel pump. You must use the heater priming harness to operate the fuel pump to prime
the system. Applying continuous power to the pump will not work
1. Attach the H
He
ea
atte
err P
Prriim
miin
ng
g H
Ha
arrn
ne
essss connector to the heater fuel pump.
2. Attach the alligator clips to the battery:
•
R
RE
ED
D to((+
+)) P
Po
ossiittiiv
ve
e B
Ba
atttte
erry
y C
Co
on
nn
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eccttiio
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•
B
BL
LA
AC
CK
K to((––)) N
Ne
eg
ga
attiiv
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e B
Ba
atttte
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y C
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n
3. Turn the priming harness switch to the “
“O
ON
N”
” position.
4. The flasher unit will operate the fuel pump (ON/OFF/ON/OFF) to prime the system.
5. Allow the system to operate for approximately 5 minutes to bleed air from the fuel lines.
N
No
otte
e:: R
Ru
un
nn
niin
ng
g tth
he
e ffu
ue
ell p
pu
um
mp
p llo
on
ng
ge
err tth
ha
an
n 5
5 m
miin
nu
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ess w
wiillll cca
au
usse
e tth
he
e h
he
ea
atte
err tto
o e
em
miitt e
ex
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essssiiv
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6. Check fuel lines and system for leaks.
7. Turn the priming harness switch to the “
“O
OF
FF
F”
” position. Disconnect the positive and then the negative battery
connections.
8. Disconnect the priming harness connector from the heater fuel pump.
9. Attach the heater fuel pump harness onto the heater fuel pump.
Figure 44.
Heater Fuel Pump Priming Harness Connections.
