ssdungeon

iTrader: (24)

Hey guys, I have a 0411 PCM in my 00 SS. No matter what my fans will not come on.
In HPT controls I can not even get them to come on.

Relays are good, fuse is good.

As far as I know, all segments were swapped when the tune was done. Is there anything you can think of for me to check in the tune?'

Any testing I can do?

brandon6.0

iTrader: (32)

Do u have your pcm wires connected as a ground trigger for the relays? Pin#42 blue i think. Also check pcm grounds to engine.

If everything is wired correctly hptuners controls should turn them on and off.

ssdungeon

iTrader: (24)

The main grounds behind the heads are there. The only ground that isn't hooked is the strap underneath by the alternator.

I may have damaged the ext sensor could that contribute? When putting it on I heard a click like I may have cracked it. My temp gauge has never worked even before this issue.

brandon6.0

iTrader: (32)

I wouldnt think they should still turn on with controls. But for them to operate normally temp sensor needs to work.

brandon6.0

iTrader: (32)

On some cars if u unplug the temp sensor, fans automatically turn on as a safety.

ssdungeon

iTrader: (24)

If they come on I'll be so happy. If the car wasn't so loud is crank it now to tell but. BIG can 3 in duals no cats just resonator and magnaflows will wake the hood.

JoeNova

Are you using the stock relays and wiring for both fans and relays in your camaro?

brandon6.0

iTrader: (32)

Snap a pic of what u have wired up

ssdungeon

iTrader: (24)

Yes I am using all stock relays. Is there another way. This is the only thing left on a 3 year project that has me not racing after several new upgrades.

relays

ssdungeon

iTrader: (24)

I'll get a pic up. Is there something additional needed from stock wiring?

I have an 0411 pcm that's Not stock but the wiring is all stock. No external relays wired.

With instructions I can wire about anything.


I just tried to unplug the ect sensor. The fans still didn't come on.

which wire will I need to ground from the fan to test the fans and which wires should pulse a ground from the ecm?

for low and high speed.

forgive me if I'm not asking the right questions. Thanks for all of your time guys.

I'll post times when I get this fixed.

brandon6.0

iTrader: (32)

The greean and blue wires should be coming from pcm. Pcm controls relays by ground.

On a 4 prong relay u have your battery #30.
U have fan power #87

One of the 2 left over will pcm ground. The other will be a jumped hot from battery or ign 12v.

These 2 prongs dont really matter orientation they can be visversa. Just find pcm ground trigger and jump it to ground. Fans should turn on.

brandon6.0

iTrader: (32)

clinebarger

Here's a 3 Relay diagram for High & Low speed fan operation, Can you post your tune?.....I would like to look at it.

clinebarger

Cooling Fan Relay #1
C3.....Battery Hot
B3.....Battery Hot
B1.....Ground Trigger from PCM (Low Speed) Pin 42 of C1.
C1.....Output to Left Cooling Fan, Should test as a ground with #3 Relay in place. Applying B+ to this pin should turn BOTH fans on a half speed.
**IF the Left or Right Cooling Fan is bad (Open), or a Bad Connection at the fans.......Low Speed operation will not work! **

Cooling Fan #2
C6.....Battery Hot
C4.....Battery Hot
B4.....Ground Trigger from PCM (High Speed) Pin 33 of C2.
B6.....Output to Right Cooling Fan, Should test as a ground, Applying B+ to this pin should turn on the Right Cooling at Full Speed.

Cooling Fan Relay #3.....MUST use a relay with a 87A Post (5 pin Relay)at this location!!!!!!
B9.....Should test as a ground through the Right Cooling Fan, Applying B+ to this pin should turn on the Right Cooling Fan at Full Speed.
B8.....Battery Hot
C8.....Open Circuit, Should have an OHM reading to C1 of Cooling Fan Relay #1 (Whatever the resistance is of the Left Cooling Fan Motor)
B10....Ground.
C10....Ground Trigger from PCM (High Speed) Pin 33 of C2.

JoeNova

Did you actually enable the fans in HPT first?

ssdungeon

iTrader: (24)

enable

Hey Joe...yes I have them enabled I had them set for the 160 stat then switxhed to 180 stat settings.

then using the 2 way controls I turned them on and nothing happened at all.

ssdungeon

iTrader: (24)

man oh man just what I needed. I'l grab a few 30a relays and test this out.

After just testing to see if the fans work at all.

ssdungeon

iTrader: (24)

Hey guys I didnt fix this yet. I have been working in NC and havent been able to work on it. However I went to the pickapart to get a replacement fuse box with the power post. Mine broke off a while ago. so i ordered and installed another universal one. There are a few blade plates that are exposed from the original power post beside the fuse box. I am not even sure how to swap that thing out. Its attached to the fuse box that the fan relays are in under the hood.

When I just cut that off another car I looked under it and noticed those blades add power to the RELAYS!!!

When I get down next weekend I will tap into those metal blades and give power from the universal distribution post that I installed. Ill try to get a pic up to show what im talking about later. But that distribution post with the red cap broke OFF on my car. I just mounted one above it on the wheel weld. I wish I had saw this before because I have done quite a bit not seeing the obvious.

How hard would it be to replace that entire fuse box with the post?

For now if jumping power to those works...I appreciate everyone that took time to help me diagnose so I feel its only fair to post my progress. Thanks guys.... after I get back to the car next week. I hope to be able to post success!!

ssdungeon

iTrader: (24)

have a great week.