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Discussion Starter · #1 ·
1988 8v n/a auto. Oh wise ones, have searched forums and exact simple solution has not been located and here's the issue: Upon turning the ignition key, before starting engine with fuelpump priming, the USA driverside cooling fan turns on, and runs continuosly, and turns off and stays off when engine shut off. No A/C--was not working when acquired. New radiator last year, along with thermostat, matching thermoswitch temp and has worked correctly until I replaced battery, new correct NGK plugs, cap, rotor, and I replaced the O2 Sensor....all without dislodging ANY other wires, and have already checked grounds and fusebox. I may very well be answering my own question but does this simply sound like a stuck thermoswitch or is there a relay I need to be looking for as well? I DO own a Bentley, but even though I have never had any overheating issues and especially now, with the fan running all the time, would like to make sure the engine is running at correct temp and cycling on and off. Note: This does not matter if it is first thing in the morning or after being driven, it consistantly comes on at the accessory point of key turn and stays on with engine running. Also, why/what changing the O2 sensor (correct bosch--no splicing) and new battery cause this? Thanks and sorry for the simplicity of this question but no ? is dumb, right? Thanks in advance. I will post pics this Summer.
 

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You say no AC but also it was not working when acquired - does that mean that AC is actually installed? ie. you have a switch on the dashboard and compressor and other bits under the hood?

If so, check that the dashboard switch is not pressed in, if so press it again and see if that changes the situation.
 

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Discussion Starter · #3 ·
Sorry, was not clear on that. The A/C is disabled, and I did already try the snowflake switch, just in-case before posting, sorry! To clarify, the 'cooling fan' that is to cycle on and off for the engine stays on, nothing to do with A/C fan.
 

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OK, it's that the left hand (US driver side) fan is switched on by the AC being activated, the right hand fan is the thermo-activated one for normal cooling. If you didn't have AC in the first place you wouldn't have the LH side fan.

You could wire it to the switch that controls the RH fan if you still want it but only for cooling, otherwise you could just disconnect it.
 

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OK, I have been able to check my Bentley and it states that the main fan that is operated by the thermoswitch will also run whenever the AC switch is on, and the auxiliary fan runs when the AC compressor is running. It seems more likely that if the thermoswitch has failed that the cooling fan will not operate, rather than operate full time.

The two other components to check would be the cooling fan time delay relay on the front left wheel housing, and the AC compressor relay at the main fuse/relay panel.
 

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First thing I'd check is to see if someone bypassed the thermoswitch and just hooked the fan up to run whenever the ignition is turned on. If that wasn't the case I'd start chasing back through the circut checking for voltage. If the wiring hasn't been bodged I'd suspect that, as you already suspect, the thermoswitch is toast. Actually, with the engine cold, just check for continuity from one side of the thermoswitch to the other -
 

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Discussion Starter · #7 ·
Thanks all--will check later today after hospital. I want to further clarify something: When I bought it a year ago, it consistantly cycled on and off the USA driver's side fan---the A/C compressor is toast and even the wire to compressor had been bodged (the red heavier ga. one), hence no belt on it due to drier was toast as well....SO, previous owner may have bypassed something to make the USA driver side fan cycle on and off, as I know by applying voltage the A/C cooling fan, USA pass. side, works but never has come on, even when pushing the snowflake, nor does my driver side fan go off when pushing snowflake. I had to replace the radiator upon first getting it as it was leaking like a sieve and put everything back according to the drawing I made and Bentley afterward, and after bleeding, as when I first got her, the USA Driver side fan cycled on and off as it should. Can someone confirm for me that as your sitting in the car, USA driver's side, that the left fan is the one supposed to be cycling on and off? Sorry, disabled veteran with foag of war in the brain this morning. Now you can see why I was having trouble getting clarity via the wealth of posts on this forum? Usually, people are having trouble getting the fan to cycle....that has never been my problem until replacing O2 and battery, which is charging fine, with no drop in anything with added load. BTW--I HAVE seen that rectangular (North and South) relay on fender by fuse panels...does that play a role in the fan cycling even with the A/C disabled? I DO understand that the thermoswitch in the upper left rad. does this job. Pretty new to Saab's, was a Jeep CJ7-early Wrangler guy for years before. Again, I appologize for long posts but it seems I am having my albeit late, my electrical gremlin's initiation...and yes, I have small spiders that cohabitate with me in car's side mirror! :)
 

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Pull the A/C Relay out, see what happens.
 

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Discussion Starter · #9 ·
Jim, I only was able to do a few things due to a procedure I had at clinic today. BUT, when I pulled the A/C cooling fan relay out, the fan stopped. I put relay back in and rechecked all fuses and then went around to wiring to see if anything perhaps was kinked or unconnected. I have not solved the problem yet but found a likey suspect: The passenger side fan that has never run, always the driver side one that has properly cycled on and off for a year until recently, has a green old heat shrink wrapping around it that goes down from that fan's (by the battery) connector, through a two piece metal wedge-like shape supporting fan motor and then goes elsewhere,; when I moved that wiring that looked like a probable kinky (sorry) point, the driver side fan stopped here and there when I disturbed the wires there...I double checked that it was not the connector to the fan itself (again pass. side fan), and it was fine with clean contacts. So for now, moved the wires back to where the fan still ran until I feel better to take a look and either rewire or see if any Saab's are still alive in our local scrapper yard. And no, do not have a multimeter but wondering if these symptoms would be caused by the two wires off that fan that works but never runs (pass. side) touch or are grounding out? I know good thermoswitches do not usually go within a year's time, so not really leaning that direction until wiring issue sorted out. Any thoughts or experiences anyone ca relate to a similar issue you have wisdom on anybody? Thanks!
 

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By pulling out the AC relay and the fan stops suggests that the issue is on the switch side of the relay. You can leave the relay out as you don't use the AC.

As the other fan only comes on when the compressor runs it should never run if you have disabled the AC, but you could disconnect it as well if you think someone has bodged the wiring.
 

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It seems more likely that if the thermoswitch has failed that the cooling fan will not operate, rather than operate full time.
When the thermoswitch on mine died over Xmas, I noticed when I walked past the car - and the fan was on. Despite it having been parked in the snow overnight.
 

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Discussion Starter · #12 ·
So logic dictates that I should run the car with relay pulled and wait for it to come up to temp to make sure the fan now kicks in when it should as before, correct? Also, wondering if the cooling fan delay relay #9558073 plays, if any, part in this...it def. looks like it is 22 yrs old, but if not broke....thanks in advance so much.
 

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As far as I can make out from Bentley:
the a/c cooling fan (US driver side) is switched on by the relay that pulls in the electric clutch on the a/c compressor; this should still happen even if there is no belt on the compressor and could explain why this fan runs continuously. If the temp control knob is set to point to the blue section at 6 o'clock and the snowflake switch is 'ON', I expect the fan will run whenever the ignition is 'ON'.

The main fan aka engine cooling fan (US passenger side), runs off the thermo switch if the a/c is switched 'OFF' (snowflake switch?) and runs continually if the a/c is switched 'ON'.

Therefore operation is:
a/c 'OFF': main fan cycles, a/c fan off;
a/c 'ON': main fan runs continually, a/c fan cycles with compressor clutch

Some quick tests:
check fuses 6 (a/c) and 25 (main fan); both are 30 amps;
with IGN 'ON', short across thermoswitch terminals with a screwdriver. If main fan runs, thermoswitch is faulty.


If fan does not run with thermoswitch shorted, check for voltage between green wire and ground. If voltage present, fan is faulty.
If voltage not present, check wiring and fan relay although the 88 may not have had a radiator cooling fan (main fan) relay.

If you get the main fan cycling properly, I'd run the a/c fan off it to double the cooling effect in traffic and avoid the higher temps to which Saabs are sometimes prone.
 

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I think the fan will only run with the A/C clutch engaged. If the belt is removed, there is a 100 % chance (with rounding) the gas has leaked out of the system and the clutch and fan won't be energized :p
 

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So logic dictates that I should run the car with relay pulled and wait for it to come up to temp to make sure the fan now kicks in when it should as before, correct? Also, wondering if the cooling fan delay relay #9558073 plays, if any, part in this...it def. looks like it is 22 yrs old, but if not broke....thanks in advance so much.
Correct. Not sure about the delay relay but the fact that the fan stopped when you pulled the relay suggest that the relay itself is the issue and that your thermoswitch has at least not failed to keep the fan on. Once you have tested that the fan comes on when the temperature has reached 90 - 90deg C (194 - 203 deg F) and goes off when the temp drops back to 85 -90 deg C (185 - 194 deg F) then you will know that the thermoswitch is working properly.
 

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Discussion Starter · #17 ·
Thankyou all, for your replies and will sort this later today. I must reiiterate that aside from the A/C fan relay faulty, the A/C definitely has no belt nor R12 in it as when I acquired her, the red wire from A/C compressor had been (still is)disconnected from where it goes toward US pass. side front, down toward's drier/rec'vr and from the beginning of my ownership, the "set-up" was the US Driver side fan cycling on and off, regardless of switch positions. I replaced the radiator soon upon acquiring her as it had an obvious leak from rotted-out bottom of rad when the thermostat opened, and replaced thermoswitch at same time, and since I had never seen the passenger side fan (US side) run, I did apply current to test and it did work, although not as orig. set-up to cycle as the main cooling fan. By the way, I DO have a cooling fan relay on left inner fender on my '88. FYI--The 'kid' I bought it from apparently only owned it a year or two, and getting any information from him, let alone finalizing the transfer of the Title, was like wrangling mad cats. Local GM (deficatation explicitive) dealer will not give free carfax for car, rather wanting to charge me what it would cost me to pay for a one-time vehicle look-up), and will at some point to satisfy my curiosity of her history, however, this never gives clues of what any 'home mechanic' may have done and I am suspecting *something* had to been altercated in order for my driver side fan to always be the one cycling on and off.
Thanks so much for your generous time and knowledge and will report back on my findings, and hopeful resolve. Fel free to add any comments in meantime. I own a Bentley but wiring diagrams are Latin to me.
 

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Discussion Starter · #18 ·
Quickly clarify: The wire I described that is bodged from A/C compressor is not simply disconnected from where it goes towards/to recvr/drier pass. side front, the red wire is only a few inches long, where someone deliberately disabled/cut wire at that point. Even with A/C not able to work (no cooler in front of rad since when I replaced radiator), doe the system require that continuity of wiring, even with A/C never working, for all to work as engineered? Also note, have NEVER had any overheating issues with her.
 

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My understanding after reading Bentley several times, is that the 'snowflake' switch provides power to energise an a/c solenoid that powers both the a/c clutch and the a/c cooling fan, and through another solenoid, the radiator cooling fan. The a/c solenoid can be energised/de-energised by other control switches (system controls, not driver controls) such as an a/c pressure switch in receiver dryer unit and the a/c antifreeze thermostat, both of which I expect would be normally closed, opening on high pressure and low temp respectively. These basically ensure that a/c system pressure isn't too high, that coils don't freeze over, etc. I think that the system pressure is responsible for cycling the a/c compressor-fan combo on and off.

The a/c coolant temperature switch in rad hose near distributor, is in the circuit after the solenoid, and interrupts power to the already energised a/c clutch only; I expect this switch is normally closed, opening on high coolant temp to open the clutch and stop the compressor without stopping the fan, which would allow coolant temp to drop.

So the 'snowflake' switch (indirectly) provides power to both the a/c cooling fan and the engine cooling fan and this power is interrupted if the system pressure goes high (cycling) or if system freezes over, both unlikely if system empty. Therefore if these switches are functional, stuck closed, or jumpered, fans will run with both ingnition and 'snowflake' switch on.

It sounds like not only were a/c components removed, but that re-wiring may have been done to the fan control switches. The easiest way to translate the Latin wiring diagrams, is to make a 2 or 3 times enlargement of the wiring diagram, then write down the names of the components next to them, using the number key page, then use colours to outline the relevant circuits. Only a few matter, and only a few components are likely to be significant. Then redraw it leaving out internal details, so you have a simple line diagram, which would help trace what's there and what's been changed.

The a/c compressor is on a separate circuit, no continuity required with fan circuits, although they feed from the same soleniod; so if wires to the compressor are cut/disconnected, shouldn't have any effect. The system switches need to be 'closed' or jumpered for a/c fan to run. The radiator cooling fan needs power supply and 'closed' position of thermoswitch for it to run (see earlier post)
 

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The Fan wiring and Relay logic differs from year-to-year and from market-to-market.
To find out how the Fans work on any individual car, you need the Factory Wiring Diagram for the particular year and market.
In General:
The Cool-Fan (right side) is controlled by the Thermo-Switch, and will also run when the A/C Compressor is energized. The Auxiliary Cool-Fan will run when the A/C Switch is selected.
The Auxiliary Cool-Fan may, or may not run with the main Cool-Fan, depending on which variant you're dealing with.
 
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