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Discussion Starter #1
There's been a lot of debating about when our SSR engine cooling fan (or fanS) come on.

I used my tuning software to open up and examine the ORIGINAL FACTORY tuning configuration that my 04 SSR was delivered with.

It turns out, that this gets pretty complicated.

First, we have one PHYSICAL fan, but apaprently, it can operate at 2 different speeds. It must be fed by 3 wires versus 2 I'm guessing. So when the software says "Fan #1" it means the lower speed setting, and when it says "Fan #2" it means the higher peed setting.

Once you look at the fan configuration table, you see the FACTORY settings in the table below. Note that where a skilled tuner recommends otherwise, I have shown, in brackets, what the tuner sets the fields to. Also, the driver for all the temperature settings below is the engine coolant temperature.

Fan #1 on: 226 (181)

Fan #1 off: 219 (178)

Fan #1 turned on along with Air Conditioning: any temp over 185

Fan #1 turn off speed: 35 (Any speed over 35, Fan #1 turns OFF

Fan #1 run on temperature: 252 (If the coolant is at 252 or above, the Fan #1 stays on even after the ignition is turned off.

Fan #2 on: 235 (194)
Fan #2 off: 227 (190)

Both fans off speed: 90 (Above 90 mph, both fans are off unless the PCM is detecting conditions that imply engine overheating

One more complication: The "AC recirculation" and "Fan 2" are tied together by the software. There is a hard to understand field labeled "AC auto recirculation", and the software descriptino for it in EFILive is:
The PCM has a few dual purpose outputs.
The A/C auto recirculation output is also used for cooling fan #2 control.
This option changes the output for either A/C auto recirculation control or as cooling fan #2.

Only the following values may be entered for this calibration:
- Fan #2 Control
- Auto Recirculation
The factory value is Fan #2 Control, which, I THINK, means that whenever the AC is set to "recirculate" (bottom part of the middle of the 3 control knobs on the dashboard), Fan #2 is also automatically turned on.

Now, notice the little logic flaw in the above table. Fan #1 has a "turn off speed" (set to 35 mph), but Fan #2 does NOT. So, when you are at speeds above 35, the 2-stage fan will run under EITHER of the following conditions:
- coolant temperature is at 235 or more (or would be if Fan #2 shut off)
or
- You have selected the "AC recirculate" button (regardless of the coolant temperature or even the ambient temperature - you could use recirculation without AC at low ambient temperatures).

So, for all practical purposes, our fan will be running ALL the time in reasonably hot weather.

In standardized quality terms, this means it needs to be good enough to support a "100% duty cycle".

Someone (Houtex) pointed out that a number of SSR owners have suffered fan failures described as a "Fan #2 failure".

Hhhmmm.

Theory:

100% duty cycle required
Failures occurring
Maybe the fan being specified and purchased by GM just is not up to that standard?

I could see one easy way it could happen. The original GM designer and spec writer did not forsee that the SSR engine would run so hot. In the Chevy pickup trucks it came from, it probably does not. So, the fan in the pickups probably does not need a 100% duty cycle. But, if that same fan, or a similar one, is therefor specified the same way for the SSR, we have instant trouble.

It is even entirely possible that GM has not traced the logic the way I did above, and has not therefore yet realized what is going on, and why they are having to replace so many fans.
 

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Great work Jim. Will you be able to check the '05 engines? I typically run the a/c on recirculate all the time, so I gues I'm covered and so far (1300 miles) the highest temp has registered at 210 at long idle, but a/c was blowing.
Hope you are still having a good vacation.
 

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Discussion Starter #3
ampmop: No one has yet, officially at least, released software that can read the 05 PCM, so I am stymied there.

Yes, the vacation has been great. I plan on driving back to Austin on Saturday and Sunday.

No new assignment or job yet though. Sigh . . .

Jim G
 

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Hey Jim

I have posted some comments on the same topic on other threads.
While driving on the freeway in bumper to bumper traffic on a hot 95 degree day, my temp guage AT IT'S HIGHEST, has pegged 235, running with NO A/C. windows down.
The other day after getting home I popped my hood and sat there watching when the fan would kick on. The first time would be around 220-225 at it's slow speed. At this first speed the fan is pretty quiet and you really can't hear it over the engine cranking. You need to look under the hood to see if it's moving. At this point the engine temp will continue to get hot while the fan still at first speed is tryijng to cool the engine down. At most the engine gets up to about 235- 238 before it is cooled down, still by this first speed of the fan. I have yet to see the fan kick into this second higher or faster speed when the engine temp it at 235-238. Does this sound normal to you ?? Does GM consider this normal operation ??
I'm thinking there really isn't a secondary speed to this fan. Looking at your numbers posted above, your right !! the fan would be constantly on.
 

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SSR Pit Crew
2004 UV
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So maybe I don't have fan failure afterall, but it sure is nerve wracking to see the temp move so close to redlineing. Have done that before, XKE - water pump, 944 Porsche - head gasket, Blazer - head gasket.

I have to drive from out in the middle of the boonies to work and back every day and do not want to be stuck in the middle of nowhere when my truck takes a dump!
 
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Since Ed tuned and reorgramed my fanson the 05, the temp has not got up to the 210 mark. This is in town with the top down, temp over 90 outside. So they can be ajusted. Ed is one of the few that has cracked several things in the new can on the 05 SSr.
 

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SSR Pit Crew
2004 UV
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BobA said:
Since Ed tuned and reorgramed my fans on the 05, the temp has not got up to the 210 mark. This is in town with the top down, temp over 90 outside. So they can be ajusted. Ed is one of the few that has cracked several things in the new can on the 05 SSr.
This is what I want...stay below the 210 mark(...which it had been doing before yesterday...so maybe something is haywire). How do I find out about this? Who can do it for me? Will it work on the 04 as well? Mine should be out of the shop Monday or Tuesday after installing a new "cooling fan motor assembly" (whatever that is)...will see how it behaves afterwards. Service tech did not give me any other info...will find out more on Monday.
 

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Bright Idea for Jimmy G.

A great detailed study by JimG. Now I read someplace that you are presently unemployed. I also read that you are coming up to the SSR Homecoming and maybe Dream Cruise. Right! Ok how about bringing your tech. equipment, setting up shop in LCC parking lot someplace and we will line up for fan check and adjustment. You could get $25.00 per vehicle and make a lot of happy drivers. I'll be first in line. (Not asking for much am I) ? Now if it turns out that we really do have a cooling problem and if a bunch of us get in stop and go traffic during the Dream Cruise, it just might turn into a Steam Cruise. I have checked my 05, 6spd. and with the A/C on my fan cycles ok. I don't know if it works with the A/C off.


Lets see what the rest have to say! :seeya Scheide
 

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Discussion Starter #11
Scheide: That is actually just crazy enough to be interesting.

I AM equipped to access and alter PCM configurations 03 and 04 SSRs, BUT you want to do more than just fan on/off to make it economically feasible.

The reason is that no matter who's tunignsoftware and hardware cable a tuner buys, he gets charged a licensing fee for every VIN he touches with it. The licensing on the EFILive software and hardware I have has about the lowest unit cost - $100 per license. HP Tuners is either $200 or $250 per license. I don't remember what the LSI Edit unit license cost is.

So, the tuner spends at LEAST $100 for the license just to access your VIN. It's only what he charges BEYOND that that actually brings him any revenue for his work and other costs.

Therefore, we'd probably want a tiered setup of some srt where you can buy different packages of software mods.

Some of the variables that I think make a lot of sense, rght off the top of my head, include:

- Fan on/off
- Gear ratio change if needed
- Adjust duration of shifts
- Adjust speeds where "normal" shifts occur
- Adjust WOT shift points (factory settings are VERY low)
- Change power enrichment delay
- Modify (NOT defeat) the torque management
- Modify (NOT defeat) the abuse management

What's the route and itinerary for the tour?

Maybe I could even get to MTI in the process to get the higher ratio rocker idea tested.

Jim G
 

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JimGnitecki said:
Scheide: That is actually just crazy enough to be interesting.

I AM equipped to access and alter PCM configurations 03 and 04 SSRs, BUT you want to do more than just fan on/off to make it economically feasible.

The reason is that no matter who's tunignsoftware and hardware cable a tuner buys, he gets charged a licensing fee for every VIN he touches with it. The licensing on the EFILive software and hardware I have has about the lowest unit cost - $100 per license. HP Tuners is either $200 or $250 per license. I don't remember what the LSI Edit unit license cost is.

So, the tuner spends at LEAST $100 for the license just to access your VIN. It's only what he charges BEYOND that that actually brings him any revenue for his work and other costs.

Therefore, we'd probably want a tiered setup of some srt where you can buy different packages of software mods.

Some of the variables that I think make a lot of sense, rght off the top of my head, include:

- Fan on/off
- Gear ratio change if needed
- Adjust duration of shifts
- Adjust speeds where "normal" shifts occur
- Adjust WOT shift points (factory settings are VERY low)
- Change power enrichment delay
- Modify (NOT defeat) the torque management
- Modify (NOT defeat) the abuse management

What's the route and itinerary for the tour?

Maybe I could even get to MTI in the process to get the higher ratio rocker idea tested.

Jim G
Let me know when you are set up for '05's, I'll come by your house for a tune up package.
 

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I'm not cool...
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dang I'm stuck in slc!

black beauty is in the shop waiting for a new fan to arrive, I'm also having them check to see if the air conditioning is getting cold enough and also the tink :confused
I would love to come to the tour and visit & tune & stuff :cool
but I guess I'll hafta just buy my own EFIlive and getr dun :flag
p.s. I did the fan 'tap' fiday night but saturday it was un-resurectable :nodno
 

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mikepowell said:
black beauty is in the shop waiting for a new fan to arrive, I'm also having them check to see if the air conditioning is getting cold enough and also the tink :confused
I would love to come to the tour and visit & tune & stuff :cool
but I guess I'll hafta just buy my own EFIlive and getr dun :flag
p.s. I did the fan 'tap' fiday night but saturday it was un-resurectable :nodno

Same thing here, waiting for a fan and having them check the A/C because it isn't getting cold enough. The cab of the :ssr is soooo small the A/C should freeze you out, even in 90+ temps. So far, (knock on wood) no tink :thumbs or my hearing is real bad :lol
 

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I'm not cool...
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lemmeno how it goes

artsmart said:
Same thing here, waiting for a fan and having them check the A/C because it isn't getting cold enough. The cab of the :ssr is soooo small the A/C should freeze you out, even in 90+ temps. So far, (knock on wood) no tink :thumbs or my hearing is real bad :lol
it's pretty booring without the ssR huh :flag
 

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not done yet

Service tech called me last eve and reported that the cooling fan motor had a short in it and fan would not come on all the time, they had to order new motor and since we live in the boonies it was expected "anytime"...have heard nothing today...had to drive around all day in a white Malibu...coworkers wondering where my cool SSR was...couldn't believe it was in shop @ only 3274 miles :eek hope to have it back by weekend...

how is your's coming along :)
 

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Retired GM Program Manager/ Chief SSR Engineer
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If someone happens to jump your vehicle by putting the positive jumper lead on the red wire that goes into the underhood fuse box, electronics can get fried and cause the fan to not work. There is a red box on for attaching the positive jumper on the right front of the vehicle. This is not an owner issue, but an inexperienced help issue.
 

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Discussion Starter #19
freezer and beer100: I posted about this a few days ago. It is a known "common error" that GM technicians charging the battery sometimes atatch the positive lead to the terminal in or near the fusebox instead of the correct positive terminal on one side of the engine. This generates spikes apparently that sometimes fry the fan control harness or nother subassembky on the SSR (sorry I cannot remember which one) because of the unintended proximity.

The point is that it is an error apparently common enough that GM saw fit to issuse a TSB about it.

You can probably find my earlier posting by doing a search on "cooling fan".

Jim G
 

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freezer said:
If someone happens to jump your vehicle by putting the positive jumper lead on the red wire that goes into the underhood fuse box, electronics can get fried and cause the fan to not work. There is a red box on for attaching the positive jumper on the right front of the vehicle. This is not an owner issue, but an inexperienced help issue.

Since my :ssr came off the production line in June '04 and I didn't buy it until March '05, it stands to reason that it had probably been jumped a time or two because it was just sitting on the lot...when it overheated and I had it taken in I made sure the service writer and tech saw the TSB about the electronics being fried due to an improper jump. Service dept assures me that this is NOT the case...we will see once I am called and told it is ready to go. Thanks to this site and all the hard work among you guys I don't feel completely lame-brained when talking to tech...

will post any updates
have a good one :seeya
 
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