1984 C20 Fuse Panel and Harness examination

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dougbert

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1984
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K1500/nv4500/np241c/33x12.50x16/4.10 Gears 14BFF
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5.3L - 2002 Silverado, rebuilt top end, long tube headers
Ive got a few of those from an 88 lesabre. and i know this is for 1984 fuse panel, im just saying what i have.

ditto from my prior post above, thanks
 

Snoots

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Just shoot me a PM.
 

dougbert

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K1500/nv4500/np241c/33x12.50x16/4.10 Gears 14BFF
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5.3L - 2002 Silverado, rebuilt top end, long tube headers
Here are my goals:

1 - Determine how to add fused circuits to my existing 1984 K1500 fuse panel

2 - Use the C20 fuse block to see how things are put together and how to take them apart. Do this on the table in order to figure out the best way to add parts to the K1500 IN THE TRUCK - still have to dismantle things

3 - Use C20 parts for the K1500 panel to add the new circuits

4 - determine how to remove the fuse clips from the C20 block

5 - add new circuits with pig tails for current and future use

6 - document where new circuits are, wire size and fuse size

First picture, we are looking at the backside of the fuse block, according to my reference grid, the columns would be labeled (left to right) as: H, G, F, E, D, C, B and A


here is the C20 block split apart
On top of the pic is the North-side wire bundle
On the bottom is the South-side wire bundle

The large orange wire in the center powers positions E1, E2 and E3

This actual is different from the colored block map picture in a prior post I made, which incorrectly stated, that this powered E1 and E2 only.

It is this hot wire that provides power to position F2, (the lone purple dot) that would power (through the circuit breaker) the Power Windows (WDO) circuit if this vehicle had the power window option. One goal is to add a circuit breaker to E2 to F2 bridge and add a wire to F2

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Close up of North-side wire bundle

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Close up of South-side wire bundle

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Here is a shot of the inside portion of the firewall bulkhead socket

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And a close up of the orange (HOT) power wire that powers block positions E1, E2 and E3
To the left of the orange wire is F2 where a new wire will go. Above F2 is F1, where the brown wire goes off to (WIPER, or other high load circuit)

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dougbert

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5.3L - 2002 Silverado, rebuilt top end, long tube headers
I think I found a picture of the Window female connection that the upper circuit breaker fits into:

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GM Part number 12004029

Found the pic at https://www.connectorpeople.com/Connector/DELPHI-PACKARD/1/12004029

1 P BLACK PACK-CON III UNSEALED FEM CONN


from Delphi - no longer available

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oh well


If any one comes across one in junk yard, they are GOLD worth
 

gmachinz

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That connector housing is worthless without the correct metal fuse insert which was obsolete before the connector became obsolete. GM deleted this unnecessary part in 1984 and instead just went with an IGN cavity source for the windows.
 

dougbert

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K1500/nv4500/np241c/33x12.50x16/4.10 Gears 14BFF
Engine Size
5.3L - 2002 Silverado, rebuilt top end, long tube headers
That connector housing is worthless without the correct metal fuse insert which was obsolete before the connector became obsolete. GM deleted this unnecessary part in 1984 and instead just went with an IGN cavity source for the windows.

yeah, that is the conclusion I came to as well.

Are you referring to the IGN column I label 'A'?
On that line, my block has a 20 amp fuse for the IGN column, not the 25 amp of the original window position.
thanks
 

gmachinz

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While the fuse panel layout itself differs slightly beginning in 1984 from what you have, the load on the IGN circuit is still the same. Or, you can simply add a control relay powered off a BAT cavity and trigger it with an IGN feed and that relay could then run the power feed for the power windows. I suspect GM felt the resettable circuit breaker was redundant and not needed-thus cheaper to remove it.
 

dougbert

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5.3L - 2002 Silverado, rebuilt top end, long tube headers
While the fuse panel layout itself differs slightly beginning in 1984 from what you have, the load on the IGN circuit is still the same. Or, you can simply add a control relay powered off a BAT cavity and trigger it with an IGN feed and that relay could then run the power feed for the power windows. I suspect GM felt the resettable circuit breaker was redundant and not needed-thus cheaper to remove it.


ah, I finally read your name in addition to your moniker. Doh!.

Jabin, thanks for the input
 

MikeB

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I have some documentation on the instrument cluster wiring and pin-outs if you need it. There are several differences between idiot lights and gauges.

I also found these Painless 73-87 wiring instructions to be helpful in understanding some circuits. https://www.painlessperformance.com/Manuals/20205.pdf
 

Camar068

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Never noticed this one @dougbert . Awesome write up.
 

Andrew Koetz

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More pics

pic 1 - Instrument Panel (IP) 18 pin male plug on the left.

pic 2 - dual tank switch connector

pic 3 - don't know yet

pic 4 - side view of panel and one of the two major wire bundles coming out

pic 5 - view onto the "top" fuse side of the assembly. This is what we see when we look up on the firewall on the dash. It is composed of the fuse holder panel and is connected to the "inside" firewall bulkhead connector, with a space between them to allow wires ingress and egress. Note the silkscreen on the fuse panel which identifies what each fuse and contact point is suppose to be. NOTE: This legend applies to this particular fuse panel.

From looking at the picture, there are (top to bottom, left to right):
(---- indicates no electric connector is present in the hole)
(??? indicates no idea what that hole provides)

ROW 1:
HAZ FLASHER | CHOKE | HTR & AC

ROW 2:
HAZ FLASHER | ---- | ??? | WDO (window ??)

ROW 3:
IGN | ---- | ACCY | AUX HTR A/C | ----

ROW 4:
IGN | GAU/IDLE | RDO (radio?) | ??? | STOP HAZ

ROW 5:
IGN | T/L CTSV | WIPER | ???

ROW 6:
IGN | TURN-B/U | HORN-DIM | ECM-BAT | PWR ACCY

ROW 7:
INST LPS (lamps) | ---- | BAT | ---- | DIR-SIG FLSH

ROW 8:
LPS (Lamps) | ECM-IGN | BAT | DIR-SIG FLSH


Some holes are fuse hole with connectors while others seem to be access connectors where special connectors can be locked into place - several such wires are present in the picture

Some holes don't have connectors while some do but are not labeled nor wired
Would the slot on "row 8" marked for LPS be for the headlights? From the way I see the "INST LPS"; this looks like the fuse for the instrument cluster lamps? My headlights are currently not operating at this time. I just replaced the pigtails and put in new headlights a couple weeks ago. The original connectors on my truck were all dryrotted out and the connections at the headlights were "questionable".
 

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