Fuse 14 2004 f150 supercrew lariat 4x4 5.4
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Fuse 14 2004 f150 supercrew lariat 4x4 5.4
I have unplugged the shifter stuff under the console i have unhooked the backuplights, I have unhooked the electrical to the heated pcv, and unhooked the a/c swithces, its an american truck i don't think i have daytime running at least not that i can see. Fuse continues to blow, i'm pulling my hair out scared its a dead short. Any advice or guidance or any advice on where to start looking for short? Oh yeah new body style.
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From: Under the flightpath of old ORD 22R
F14 feeds ( on a 5.4 Auto )
DTR switch ( which feeds the backup lamps )
Heated PCV valve
ABS control Module
AC high pressure switch ( not the HVAC control module in the truck )
De-activator switch for the cruise control
DRL enable relay
From your post, I can say you ruled out the Heated PCV valve itself ( not the wiring ).
What AC switches did you unhook ?
Do your headlamps come on at a lower brightness when you turned on the truck before ? Check the Aux relay box for a DRL enable relay in it to verify if you do not know.
The reversing lamps are fed from the DTR, so a lot was skipped with unplugging the reverse lamps.
1. Start with unhooking Connector C270B at the CJB ( aka Central Junction box , cab fuse panel ). It is a 12 pin ( 2 rows of 6 ) black cam over connector, place a new fuse in F14, turn on the truck to see if it blows.
- This step removes all wiring and items.
- If tests OK, turn off truck and re connect C270B
- If it blows, the problem is in the CJB some how.
2. unhook Connector C110 on the transmission.This is a 12 pin square gray connector ( would look like it is 4 rows of 4, but is is slightly different on the inside, 2 pins + 2 rows of 4 + 2 pins )
- This will remove the remainder of the wiring to DTR.
- With good fuse in F14, turn key to run position see if it blows
- If not works towards the DTR for the short.
3. Unhook Connector C139 which is in front of the PCM connector on the firewall, RH rear side of the engine compartment. This is a 16 pin ( 2 rows of 8 ) black connector.
- This removes the wiring to the Heated PCV valve.
- With good fuse in F14, turn key to run position see if it blows
- If not work towards the PCV for the short.
4. Unhook the ABS Control module
- Test
Another route is to unhook all the items, and unplug from the CJB, and test the circuit for a short to ground. The splice is a 7 way single splice point which looks to be inside the cab, at the firewall next to the PCM ( up high under the dash just to the right of center line ) ?
DTR switch ( which feeds the backup lamps )
Heated PCV valve
ABS control Module
AC high pressure switch ( not the HVAC control module in the truck )
De-activator switch for the cruise control
DRL enable relay
From your post, I can say you ruled out the Heated PCV valve itself ( not the wiring ).
What AC switches did you unhook ?
Do your headlamps come on at a lower brightness when you turned on the truck before ? Check the Aux relay box for a DRL enable relay in it to verify if you do not know.
The reversing lamps are fed from the DTR, so a lot was skipped with unplugging the reverse lamps.
1. Start with unhooking Connector C270B at the CJB ( aka Central Junction box , cab fuse panel ). It is a 12 pin ( 2 rows of 6 ) black cam over connector, place a new fuse in F14, turn on the truck to see if it blows.
- This step removes all wiring and items.
- If tests OK, turn off truck and re connect C270B
- If it blows, the problem is in the CJB some how.
2. unhook Connector C110 on the transmission.This is a 12 pin square gray connector ( would look like it is 4 rows of 4, but is is slightly different on the inside, 2 pins + 2 rows of 4 + 2 pins )
- This will remove the remainder of the wiring to DTR.
- With good fuse in F14, turn key to run position see if it blows
- If not works towards the DTR for the short.
3. Unhook Connector C139 which is in front of the PCM connector on the firewall, RH rear side of the engine compartment. This is a 16 pin ( 2 rows of 8 ) black connector.
- This removes the wiring to the Heated PCV valve.
- With good fuse in F14, turn key to run position see if it blows
- If not work towards the PCV for the short.
4. Unhook the ABS Control module
- Test
Another route is to unhook all the items, and unplug from the CJB, and test the circuit for a short to ground. The splice is a 7 way single splice point which looks to be inside the cab, at the firewall next to the PCM ( up high under the dash just to the right of center line ) ?