2001 SL1:

Radiator fan does not work at 200 degrees when car is idle. I turn on the heater and I get cool air. However, when I'm driving, the heater does work and blow hot air. I am having some tensioner issues with the belt squeaking. Is there a possibility that the overheating issue is because the tensioner needs replacement, and the car is not working at its optimum capacity? Are these 2 issues related?

Also,
In the past was having fan issues, my A/C needs servicing, so they put a charge in the compressor, and the fan immediately engaged. I couldn't afford to fix the A/C, so the mechanic added a relay switch so the fan to manually turn on. However, the fan did engage at 200 degrees w/o using the switch and never needed it. Is there a possibility that the A/C charge lasted this long (2 years) and the slow leak is creating the anomaly again? Is the A/C and the fan functionality interdependent? So, if the A/C is not working (needs servicing) the cause of the fan being inoperable?

Yesterday, I replaced the fan assembly because motor tor was faulty. When I turned on the ignition, the fan did not engage at 200 degrees. Fan manually engages when manually flipping the added switch.

Thoughts?

 

1. I replaced the tensioner. That dashboard lights up like a Christmas tree. I'm receiving a better charge, now. No belt squeals.
2. I replaced the ECTS (AC Delco part). I thought the fan would turn on at approximately the 12-12:05 o'clock position with a new sensor. But the fan never engaged. As the temp dial was approaching the 1:00 o'clock position, I manually engaged the fan with the installed switch.

So, new fen, new tensioner, and new ECTS. The fan doesn't turn on at its recommended temperature.

 

Have you tried replacing the thermostat? It COULD be that simple. I don't think the A/C is related to what's happening, but I'm NOT a mechanic. I don't know diddly squat about the a/c systems in a car.

 

I turn on the heater and I get cool air. However, when I'm driving, the heater does work and blow hot air.

Try filling up the radiator.

 

1) AC is related, jump out your Low PSI switch, it's by the battery.

2) Assuming yer water pump is circulating water in the CRT, which confirms thermostat is working try burping the system, elevate the front end or just the pass side wheel on a curb or sumthin and get all the air out
3) Take 2 shots and call me in the morning........

 

I doubt we hear from him again. Likely just needed some coolant.

 

Don't know where you are getting temperatures from to correlate to dash indicator temperature gauge. 12:00 is not 200° or even close. My s cars get past the third tick on the gauge before the fan kicks in. This is directly related to the ECTS sensing the temperature of the coolant. The fan will also switch on when the AC is engaged as long as the compressor actually turns on. This is to keep the additional load from the AC from overheating the engine. Those are the two operational modes so there are two different signals that activate the fan relay.

​​​​​​If somebody wired you a switch, it is usually because sometimes the PCM output goes dead and so the fan is never requested to turn on. If you have a switch, use the damn thing.

 

What gr said..........

 

Derf: The first op mode is applicable since the AC needs servicing. The temperature vs 12:00 o'clock was an inaccurate estimate. I should've stated the "O'clock" description. Regardless of temperature and during warmer weather in the past, I've had the fan engage at 12 o'clock and just before this issue occurred, at 12:03 to 12:04 during the warmer days last week, Although, the switch is only a band-aid to a bigger issue and until I find what the anomaly is, I'll use the switch. You mentioned some key items, Coolant, and PCM Output, I have been ignoring maintenance, so I'll probably do that next week and follow the other suggested posts. Meanwhile, I'll jumper the fuse box and verify signal to the fan and verify signal to the ECTS connector. The ECTS sensor and the Relays are showing resistance data on the DMM. It will be a while until I respond with an update. Thanks.

 

I was assuming the mechanic put in the switch because the request from the PCM was not coming when it should. If it was done because they had no clue how it was configured, that's a different story. My AC hasn't worked for years, but that does not stop the PCM from responding to the ECTS signal and closing the relay for the fan, turning the fan on. On some older Saturns, some folks seemed to run into an issue where the ECTS signal was in the right range but the PCM would never ground the relay for the fan and turn it on. So they all put in manual switches.

Remember that the ECTS is reading the temperature of the coolant in one location in the head. If the flow is restricted, say by a half open thermostat for a stuck half open thermostat, you will not be getting sufficient flow through the cooling system such that the output of the ECTS will be a true representation of the average temperature of the system. It will also not be a true representation of the system temperature if you are low on coolant if the sensor is not properly submerged all the time.

What is the resistance across the ECTS with the engine cold? Please include ambient temperature.