Radiator and engine compartment fans coming on and staying on, when cold

[jchapura]

My 2005 C2S 997.1 has been sitting for a few months. It has been on a CTEK battery maintainer. I took it out for a one hour drive today. Just after engine startup, at the end of the drive, and another engine startup after a two hour rest in the garage (water temp gage showing about 120degF), it exhibited symptoms I'd not seen before.

 

Immediately at startup with a cold engine, the engine compartment fan came on and stayed on.

 

About 30 seconds after engine startup, both cold engine and warm engine, both radiator fans came on and stayed on.

 

I have a Durametric and captured the following fault codes while the engine was running (I traversed every menu item on the left of app window):
C140
C141
C131
C152 (I think this is due to the inactivation and removal of the PASM module when I converted to coilovers)
8004
8028
8029
8042

 

FWIW, I was not in ECO mode so the air conditioner compressor was probably running. I was trying to recirculate the freon and oil. (I usually run in ECO mode.)
FWIW, there's no CEL indicator showing on the instrument display.

 

Engine water temp about 105degF.
Started engine.
Engine compartment fan is on.
Within 30 seconds both radiator fans roaring (seemingly like they are on high).

 

Using Durametric, went to Front/Activations and found 3 "Radiator fans" (not sure why there's 3). See pic below.

First entry - clicked STOP. Nothing happened.
Second entry - clicked STOP. Nothing happened.
Third entry - clicked STOP. Nothing happened.

 

First entry - clicked START. One of the front fans (or maybe both, it got quiet) slowly spun down and then 10 seconds later it went back to high.
Second entry - clicked START. One of the front fans (or maybe both, it got quiet) slowly spun down and then 10 seconds later it went back to high.
Third entry - clicked START. Nothing happened.

 

Toggling the ECO button on the climate control didn't seem to make any difference.

 

Gas has Stabil in it.
Battery's installation date is July 2014.
Yesterday, after the battery-maintained multi-month inactivity, the car acted OK - normal starter rotation speed and fire-up time.
Today, battery's voltage after sitting all night, NOT on the battery maintainer, is 12.67v.

 

Why might these fans be acting abnormally?

 

Edited March 23, 2023 by jchapura
Added tags

[JFP in PA]

Load test the battery; a nine-year-old battery is always suspect..........

[jchapura]

4 minutes ago, JFP in PA said:

Load test the battery; a nine-year-old battery is always suspect..........

I don't have a specific battery load testing tool. Nor a recording multi-meter to capture the voltage while cranking the starter.

 

Is there any risk to taking the battery out of the car and taking the battery to an auto parts store to use their load tester? For example, will any computers/settings be (semi-permanently or permanently) lost that would then need a PIWIS to get going again?

 

Or, should I buy a battery load testing tool? I see they range from $40 (no-name on Amazon) to $130 (Foxwell BT705)?

 

Or, should I just buy a new battery?

 

[jchapura]

When the current battery dies, the battery I'm thinking about getting is an Optima Yellowtop.

[JFP in PA]

4 minutes ago, jchapura said:

I don't have a specific battery load testing tool. Nor a recording multi-meter to capture the voltage while cranking the starter.

 

Is there any risk to taking the battery out of the car and taking the battery to an auto parts store to use their load tester? For example, will any computers/settings be (semi-permanently or permanently) lost that would then need a PIWIS to get going again?

 

Or, should I buy a battery load testing tool? I see they range from $40 (no-name on Amazon) to $130 (Foxwell BT705)?

 

Or, should I just buy a new battery?

 

Just about any auto parts store can test the battery for you for free.

 

If you remove it from the car, the car can relearn everything it needs to by itself, with the exception of the radio security code on cars that need one.

[jchapura]

3 minutes ago, JFP in PA said:

Just about any auto parts store can test the battery for you for free.

 

If you remove it from the car, the car can relearn everything it needs to by itself, with the exception of the radio security code on cars that need one.

Would you agree that the 2005 997.1 should not need a radio security code?

 

[jchapura]

6 minutes ago, JFP in PA said:

Just about any auto parts store can test the battery for you for free.

What is your "throw away" voltage when on the load? Less than 9.6v?

[JFP in PA]

Modern digital load testers typically simply readout "good battery", "questionable battery" or "bad battery"; load test voltage readouts are a bit "old hat".  They will also give you % data on "state of health", "state of charge", remaing CCA, and internal resistance values; on an old-style load tester, I would question the viability of any battery that drops below 10.5 volts during the test.

 

[JFP in PA]

20 minutes ago, jchapura said:

Would you agree that the 2005 997.1 should not need a radio security code?

 

Depends upon what model radio is in the car, Loren can probably answer that better as he handles radio codes, but I don't think a 997 does..........................

[jchapura]

1 minute ago, JFP in PA said:

Depends upon what model radio is in the car, Loren can probably answer that better as he handles radio codes..........................

@Loren Loren, I have the Bose system...would it need a radio code after changing out the battery (disconnected for a few hours).

[JFP in PA]

You need to post that in the "lost radio code" forum section, it won't be answered here.

[jchapura]

I took out the battery and I had it load tested at two places.

The battery is a NAPA Legend that has 765CCA.

 

Place 1:

Tested good.

Voltage sagged to 11.5v.

 

Place 2:

Tested good.

Voltage sagged to 12.2v.

 

Where to go from here to solve the "fans" problem?

 

Edited March 24, 2023 by jchapura

[JFP in PA]

I'm amazed that a battery that old is still good, but the results are the results.  At this juncture, I would suggest putting the battery back in the car and then using the Durametric, clear all the codes.  Then take the car out for a run and see what, if any, codes come back.  Sometimes these cars throw a bunch of codes for unknown reasons after sitting for a while, but if the codes are real, they will return and we can go from there.

[jchapura]

I cleaned the battery posts and cable ends.

I refitted the battery into its position.

I cleared all fault codes with the Durametric.

I started the car (in total, I idled it about 10 minutes).

Starter rotational speed and engine start-up time were all normal.

The PSM error was displaying on the instrument panel.

Within 30 seconds, both front radiator fans turned on high, and remained on during the 10 minutes.

I cleared all the fault codes.

Toggling the ECO switch on the climate control made no difference to the radiator fans being on. I left it in ECO mode.

The engine compartment fan never turned on during the 10 minutes.

I cleared all the fault codes.

After the last "clearing" of the fault codes, these fault codes were seen:

C141

8023

C140

C131

 

Thoughts? What can I check/do next? I'm perplexed.

 

[JFP in PA]

That is a weird set of faults:

 

C141 is for no power to te PCM

C140 is for the the dash communications display

8023 is full with the AC air recirculating flap motor

C131  is for a gateway controller fault

 

I almost looks like the dash internal communications are suffering electrical faults, possibly due to a problem with the system gateway contoller.  I may be time for a PIWIS scan, which would give more definitive information.

[jchapura]

On 3/25/2023 at 3:14 PM, JFP in PA said:

...which would give more definitive information.

Well, John, I continue to be stumped...

 

One last attempt to learn more before taking it to a shop, I took it out for a 30 minute drive. (FWIW, the climate control was in ECO mode.) As expected, thirty seconds after start-up, the radiator fans turned on high. About 1 minute later, the fans turned off as I was driving very slowly out of my property. (And the PSM Failure dash warning also turned off.) At various stop signs, no radiator fans could be heard. After pulling into the garage at the end of the drive, while idling, neither the radiator fans nor the engine compartment fan were on - on would have indicated continued abnormal operation of the fans (because it's cool outside).

 

...just stumped (about the original problem).

Edited March 28, 2023 by jchapura

[jchapura]

My car's been in the shop a few days to try to diagnose the issue. I picked it up today.

 

It was the air conditioner (high) pressure sensor switch - it failed in a way to indicate a high pressure and that caused the computer to command cooling the Freon with the condenser and radiator cooling fans on high. And the high pressure indication was in the presence of the system that had no Freon. The lack of Freon was odd because I remember the A/C cooling the car the last time I drove it in the Fall and despite the fact that the system held vacuum for 30 minutes (after the pressure sensor and drier were replaced) and a sniffer could not find a Freon leak after the system was recharged.