The
wiring step is the most challenging step. I say it is challenging and time
consuming but I enjoy it. This is what I have been working on for about the
last 4 weeks. This is why there has been a gap in my blog posts because while
you are wiring and trying to figure things out it is hard to write about it and
it does not seem to transfer well to the internet.
.
I started with a complete 2000
Camaro LS1 engine and body harness that I had bought from a fellow racer. Once
I had the harness I bought a 2000 F body factory service manual off ebay. The
best $60 bucks you will ever spend. Sometimes they are as high as $150 but
nothing beats the factory service manual. EVERYTHING about the car is in the
manual somewhere.
Step
1 was to figure out what was on the engine harness. I took the harness and laid
it out on the engine and started plugging in what was obvious. Injector,
connections, alternator, etc. By the
length of the harness leads and the shapes of the connectors you can figure out
most of the rest. There were a few connectors on the harness that were cut off,
these where a mystery.
Step 2: I then removed all the
black corrugated covering and tape holding the harness together. Leave some
tape or zip tie the harness together at the junctions otherwise the harness
becomes a huge mess. I removed all the covering because the next step is to
trace the cut wire leads determine what is missing.
Step 3: I began tracing the cut wires
back through the harness to figure out what they went to. What was missing
where the secondary 02 sensors, crank position sensor, Vehicle speed sensor and
backup light switch. I was lucky and they all traced back to the PCM. By using
the attached system wire diagram I was able to clearly determine what each item
was by the pin out on the PCM.
Step
4: this step was to repair the harness. I determined what was missing then I
got the replacement connectors at my local salvage yard. I knew what I was
looking for and went armed with a set of wire snips and found a 2002 Chevy truck
with a 5.3. Most of the connecters where still on the engine, Some other
connectors I got off some other nearby cars in the salvage yard. I was sure to
get plenty of wire so there was ample room for splicing. Total cost was about
10 bucks for all the connectors. I then soldered the connectors on the harness.
These connectors are way too important to rely on crimping connectors. Do
yourself a favor and learn how to solder. See How to solder post.
Step
5: No that the harness was repaired and is sitting on the engine I then started
to figure out what was needed and what could be cut out. Some people like to
tape up connectors that are unused and some like to remove that portion of the
harness. I choose to completely remove the unused portions of the harness to
simplify the harness. I first removed the AC portion. I traced the wires all
the way back to the PCM and common grounds etc. Be careful doing this and be
110% sure you can remove the items you are cutting out. I had the factory
service manual I bought off Ebay ($60) and found the circuits in the manual and
was absolutely sure they had no impact on function. I also removed the EGR
purge and backup lamp, skip shift and A.I.R.
Step
6: There are 5 major connectors to the
engine controls harness. It is through these five and only these 5 that makes
the engine run. When I speak of the engine controls harness I am not talking
about all the harness under the hood. I am only talking about the harness that
lays on the engine and hooks up to items attached to the engine. The five
connectors are the C100, C101, C105, C220 and C230. Each connector has around
10 cavities and a description of the pin outs of each connector can be found in
the service manual. You can also find pin out descriptions online with some digging.
LT1SWAP.com has a lot of good info and had a great description of 2000 Camaro
Engine harness connectors. See Attachment
With
the descriptions I was able to map out what was needed and what could be cut
out. I then followed step 2 but on the under hood harness for connectors C100,
C101 and C105 and the under dash harness for C220 and C230. With the C100
connector I took the corresponding portion of the connector and traced the
wires I needed to the termination points. See the attachment. For the C100
connector there were only 4 of the 10 wires I needed. Two where fused inputs
that I traced back to the fuse box and I cut the wire at the fuse box. The
other two where relay control wires for
the cooling fans. These are the two wires that the PCM send a signal to the
relay to turn on the cooling fans. I traced these two wires back to the relay
and cut the wire at that point. I labeled the wires and moved on to the other
connectors. After completing all this I began building my fuse box and power
station.
Step 7: Fuse box and cutoff switch: At this point I
needed to decide where to put the fuse box and cutoff switch and battery and
common grounds. Once these locations where decided for various reasons I was
able to begin laying out my wiring. I started with the power source and ran the
battery cable from the battery to the cutoff to a power lug next to 3 fuse
boxes holding six fuses. Two fuse boxes have power coming off straight off the
cutoff switch and one fuse box is only "on" when the ignition switch
is on. This fuse box powers the PCM and all the fused wires that I pulled from
the connectors I described in Step 6 .The other two fuse boxes power stuff like
wipers, headlights, horn, fuel pump and fan relays, brake lights and gauges. I
did not want any grounding issues so I created 4 central grounds by welding
bolts to the rollbar cross tub and the floor so I could ground all the wires in
these known locations.
Step
8: Actually running the wire. This step took forever and was a lot of
soldering. First I listed what needed power and figured out how many fuses I
needed. Then started running the wire from the fuse box to all the locations
that needed to be powered. For the gauges I created a mini harness complete
with a 10 pin connector so I could easily remove the gauge cluster if needed
and also remove the entire dash panel easily. Do yourself a favor and don't
wire through the dash or around the roll bar. Make sure all your wires are on
the same side of the roll bar or whatever so you can also remove the harness
without cutting it. This step is by far the most time consuming but is not
hard.
Step 9: Testing and
bundling. Before I started bundling the wires I wanted to make sure everything
worked so if I had trouble I could easily identify the wires and fix if needed.
This was good because I had wire the fuel pump incorrectly. When I first fired
the engine the fuel pump would only run when the ignition switch was off. I had
mistakenly run the relay so it was switched to 12v and not to ground as it
should be. Problem solved and with the wires unwrapped it was easy to make the
correction. The engine runs great now and will wrap all the wires and make sure
the harness has no rubs binds and is clear from the exhaust.
Misc stuff. Since this is a
race car I wanted to make sure that the brake lights where good and bright.
Since I was not going to use turn signals any longer I wired the brown, green
and yellow wires together to the brake switch. This way all the filaments will
light up when hitting the brake. Easy to see in race conditions.
Wipers: Here in the Midwest wipers
are a must. We have a least one rain race per year usually two or three. On GM
cars the easiest thing to do to wire the wipers is trace all the wires from the
wiper motor back to the connector under the dash. This connector then go to the
steering column and up to the switch on the stalk. All the electronics for the
wiper function are in the stalk switch. The delay, park and multiple speed
functions are all there. The only thing you need to do to make it work is
provide power to the yellow wire on on the connector that goes to the column.
You will also need to ground the black wire. That is it nothing else is needed
and the system will stand alone.
