S60 T5 air cond and...

edifice · Post by **edifice** » 24 Jan 2018, 08:37

Hi
Mine is 2007 S60 T5

When driving at slow speed and stuck in traffic jams, i need to switch on the aircon. If aircon is off, the coolant temperature rise up to 100 c before radiator and up to 85 c after radiator.

If aircon is on, normal coolant temperature is 85-89 c before radiator and 55-65 c after radiator.

Also if aircon gas is empty, the coolant temperature gets high.

It seems that if aircon is off or aircon gas is empty, the fan speed is slow...not enough to cool down in traffic jam.

What is relation between aircon system and coolant temperature?

I did replace new radiator, new fan, thermostat,

Ambient temperature here average 35 to 38 c

Help. Thanks

Post by **oragex** » 24 Jan 2018, 09:18

The thermostat starts opening around 85C and is fully opened at 91C. This would be the temperature before the radiator, so 100C is high, usually it should not go past 93C or so even when revving the engine.

When the coolant is hot, the coolant sensor should run the fan at speed even with the aircon off. Depending on the car speed and weather, the aircon itself will also trigger the radiator fan for itself to cool a little bit the refrigerator. From your description it looks like actually only the aircon is helping the coolant cool down a bit, the engine Ecu or coolant sensor don't seem to be triggering the fan properly.

I assume you had the whole thermostat housing replaced, along with the coolant sensor. Was it a Volvo unit? There may be air trapped around the sensor causing it to misread the temperature. From a cold engine, does the temp gauge climb at a steady and slow rate as the engine is warming up?

edifice · Post by **edifice** » 24 Jan 2018, 10:45

Thank you for reply

I changed thermostat, housing and coolant temperature sensor. Wahler OEM. Coolant temperature sensor is original Volvo

My mechanics also confused

I have two set of radiators. 1 is original. Another 1 is high performance 2 rows. Both radiators didn't help also

Reading of coolant temperature before radiator is by Ultragauge. Reading after radiator i install sensor at coolant return hose and use Shadow meter. Both Ultragauge and Shadow are working fine.

Yes, from cold start, the temperature meter climb steadily and slow down when reaching optimum coolant temperature

The Ecu is already remapped. Do you think this problem is related to Ecu?

Anyway this problem only gives me big worry if in case the aircon system breakdown...because when no aircon, coolant temperature sure will rise. A nightmare if traveling long distance

Post by **abscate** » 24 Jan 2018, 10:58

It sounds like the fans arent coming on correctly to cool your radiator.

35C is Hot HOT HOT for ambient....are you in Middle East??

Post by **oragex** » 24 Jan 2018, 11:44

edifice wrote: ↑24 Jan 2018, 10:45 The Ecu is already remapped. Do you think this problem is related to Ecu?

I remember someone having a similar issue, good coolant sensor, the fan still wouldn't kick in. I'm not sure about the ECU, a specialist could perhaps check this possibility. One thing that's perhaps easier to check is when the coolant overheats, to check the wires between the ECU and the fan unit see if there is a voltage.

edifice · Post by **edifice** » 24 Jan 2018, 17:53

Thank you

Im from Malaysia