good day all,

it appears that when the temps creep up past 75 degrees and when i am just creeping along in traffic (a little quicker than stop and go) my engine temp creeps up past the 3 clock postion almost hitting past 2 but not overheating.

in 100 degrees sitting in my driveway for 2 hours (locked out) no problem or driving on highway no problem

I have flushed the system twice in a year, changed thermostat and temp sensor by the thermostat housing with OEM parts and pressure tested the system no leaks (had a leak by hte small elbow near the top of the radiator several months back but replaced that hose (oem part also)

i have researched that it may be a fan relay issue but i cant seem to find the location or where to purchase this part ...if that is what is wrong? both fans do turn on at times, odd when its cool outside i was under the impression that the second fan always comes on when the ac is turned on?

 

how many fan relays does the 2002 volvo s40 have I seen relay in the fuse box and several sites point to another 5 lug harness type relay?

 

does your fan come on as expected and does it stay on after you turn off the key? Its also possible the ECT sensor is acting up - I've had that cause the gauge to wander and to have the after run fan come on.

 

Well your fans work , you have flushed the radiator and changed the thermostat , so one would think all should be fine .
However its a 20 year old car and this is a restricted coolant problem , when idling the engine does not require a lot of cooling so should be fine , on the motorway lots of air flow so no problem when in top gear cruising., try to drop a gear or 2 on the motorway and if the same problem then its either.
1 Faulty thermostat (you changed it so hopefully its good)
2 Water pump (this should be changed during the cambelt service)
3 Radiator is partially blocked due to age (it will still flush )

Heavy congested roads are really bad for the cooling system .and will show up these defects

 

Thanks so much that may be my last part that I haven't looked into in changing the radiator it maybe partially clogged but one mystery I have is where is the relay for the hi and low speed settings of the fan ? I ordered the part which is the same in every vendor sites and it's sort of big with 5 lugs standard intermotor RY563 ??? I spent 2 hours under the hood looking for its location ???

 

- 2 relays - one for high and one for low speed. (and 1 for the ac compressor) I've circled the two speed fan in red. All relays (that are used) are located in the fuse/relay box under the hood. Note all of them are supplied a ground from the ECM to close the relay when needed

 

Thank you so much so odd that all online vendors including Volvo specific ones don't mention the ones the under hood fuse box and refer to the relay I mentioned earlier which seems to go somewhere near the front of the vehicle and seems large. The ones in the fuse box are just as hard to find at any store also jus not my luck it seems
but I would be replacing that 20 year radiator seems to be the weak point in the system right now hopefully I can purge/bleed the system correctly I recall it being a specific process to get all the air out by using that bleeder valve on the lower hose ? hopefully I get it right the first time

 

Thank you so much!! if I am reading this correctly then there is a total of 3 relays position 1 speed 1 (low?) position 4 speed 2 and position 3 for the ac fan

awesome thats more information i have received about this in almost 4 years including from 2 volvo dealers

is the engine fan always on ? and then on demand like higher temps or ac use then it kicks in? cause my engine fan (i guess the smaller white one on the passenger side appears always on but i cant see the difference between the 2 speeds??

Biggest question yet where can I find these relays every store lists them different names and functions?? is there an OEM number since the only number i found is volvo OEM 30870937 and 30870938 rear defroster and muli purpose micro relay?

 

In the diagram the dashed lines are possibilities - the market your car was built for may not all of those parts. For instance it shows 3 radiator fans (6/9, 6/26 and 6/27) - you only have 2. Perhaps a single fan is used in a different market without ac.

For relays - a lot of those have the same part number - if you think you have a bad one - just swap with another - if the thing you want to work starts working and the thing the relay controlled stopped - !!! you have a bad relay, diagnosed at no cost. Here's a partial list of relay part numbers. BTW all this info can be found in the stolen and hacked version of VIDA easily found on the internet or through several vendors.