2000 s80 2.9 Radiator fan not working (non turbo)

[mhanny]

Fan is not coming on regardless of coolant temperature but comes on when A/C is turn on. Temp
gauge on dash goes up midway then engine speed don't go any faster than about 2k even if car is not driven. Is the ECT sensor located right below camshaft gear behind belt cover? Not positive about that cause I don't have the wiring schemat. Can't locate any repair manual to identify components of wiring schemat found in our forum. Also is rough idling and misfire like engine operation a "limp mode"? Would a bad left upstream O2 sensor cause a limp or rough idling?
Any suggestion from you guys are appreciated greatly. Thanks and have a great weekend to all.

P. S.
Actron OBii codes;
P1603, P1608, P0134, P0135

[Oly_850]

Hello yes the coolant temp sensor is screwed into the thermostat housing below and between the cam gears. The Torx bolts are easy to strip so use a 1/4 drive small ratchet, and lift out the coolant / power steering fluid containers out of the way.

If your coolant gauge works, the temp sensor is not the problem I think. The cooling fan is controlled by a dual relay, one side controlled by the ECU based on coolant temp, the other by the A/C system. You may just have a bad relay.

The 134, 135 codes are O2 sensor faults and can make your ECU fail to meter fuel properly, which will make it run poorly and get terrible mileage.

[mhanny]

Thanks much Oly 150, I'll chk all my relays and post result.