IPD sale XeMODeX - Experts in Volvo Electronics
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy anything with this and it helps MVS!

Fan Delay in cooling, please help

Help, Advice, Owners' Discussion and DIY Tutorials devoted to the second generation C70, S40 and V50 Volvos -- awkwardly model year 2004 ½ onwards -- plus where to go for advice and discussion on Volvo's sporty C30 Coupe powered by Volvo's ubiquitous inline 5-cylinder power plant.
Posts: 26
Joined: Thu Dec 13, 2012 5:30 am
Year and Model: XC90
Location: Accra
Has thanked: 0
Been thanked: 0

Fan Delay in cooling, please help

Post by forumoto » Fri Jun 03, 2016 2:34 am

This car 2005 S40, the fan is not coming on by the temperature sensor until it get to 227 fahrenheit hotness before the ecm turn on the fan, and by then the water will over boil,

i have replace the engine coolant temperature sensor, yet still, the thermostat also have being replace yet still, the fan does not come on at 100 degree but 227 Fahrenheit and this make the car overheat and get the water boiling and getting off from the expansion tank,

i have change the expansion tank cover too yet still, please i need help..

one thing that i have seen is that when i unplug the ect sensor the fan come on immediately, and it does not boil as well.

please what might be causing the system not to start at 100 degree but rather goes to 227 Fahrenheit before, which to me is too much and the engine also boil.

Further testing on the sensor, in hot boiling water on stove with DMM shows that

at boiling temperature i get 184 ohms reading on the sensor..

this reading should even trigger the fan on, but it wont do so,

i picked up normal ohms resistor of 150 ohms, when i plug this to the engine sensor harness, the fan comes on, please advice me what might be causing this, at least 184 should still shot out the fan, but it does not but when i put the ohms resistor and start the car, immediately the fan come on

MVS Moderator
Posts: 13424
Joined: Thu Mar 31, 2005 7:14 am
Year and Model: '98 S70 T5 '07S40T5
Location: Knoxville, TN American but born in Japan
Has thanked: 7 times
Been thanked: 25 times
United States of America

Re: Fan Delay in cooling, please help

Post by MadeInJapan » Fri Jun 03, 2016 8:27 am

What brand of ECT did you replace and what thermostat?
Not on our S40's but on earlier Volvo's I had similar problems with some aftermarket parts for these... only good quality OEM works... I would look into that- could be your problem. Plug on the ECT connector can also get corroded so check for that and that there is no black/burned connections.
'98 S70 T5 Emrld Grn Met/Beige Tons of Upgrades Mobil-1
'04 V70 2.5T Red/Taupe Some Upgrades Mobil-1
'07 S40 T5 AWD 6 speed manual! Silver/Black Stage1 Heico & Elevate
'07 S60 2.5T Blue/Taupe- my kid's Volvo

Post Reply
  • Similar Topics
    Last post