This 2003 Ford Focus came in with the complaint that the car was running hot. It has a 2.0 liter engine and is a non SVT model. Although similar to later model vehicles with the same set up, this year is unique in it’s wiring harness design. After asking multiple questions of the owner and doing some basic inspection I found that the coolant was not boiling over but the temperature gauge was reading quite high. After determining that the cooling fans would come on at high speed at a temperature of 250 degrees, I decide to start investigating the low speed fan operation and started with checking the low speed fan relay. It is the light gray square relay in the center of the picture.
After removing the relay I found that the center plastic was slightly melted. Close inspection found that the terminal was not fully seated and had been making a poor connection, hence the heat damage.
Time to open up the box and see what is going on. I started by removing the intake breather tube and air filter cover. Then I could access the 7 mm headed screw to the left of the fuse box in the following picture.
Next, I released the holding clips on the opposite end of the fuse box.
After separating the retaining clips that held the two halves of the box together I was able to see inside the rear of the fuse box. The wiring looked pretty good so I decided to push the wire back into place and see what I had.
The terminal pushed back into place without too much effort so I knew there was a chance it would be usable.
To confirm the terminal was okay I inserted a jumper wire and tested the terminals drag resistance. It was okay.
I installed a new relay and held the wire in place with my pliers to make sure it would not back off.
If I had to I could have cut,spliced and moved all of the wiring to the empty relay cavity but that is a huge amount of work and everything currently is okay.
On to confirming the repair. Well things are not going so well. The temperature is up to 238 degrees and the low speed fan has been commanded on but the fans themselves are not on.
Now the engine is up to 244 degrees and the medium speed has been commanded on and still no fans on.
Now we are up to 250 degrees and the high speed fan fans have been commanded on and the fans are finally on. This is what I had originally discovered in testing earlier. My guess now is that the relay and wiring problem I had found earlier had probably been caused by some one else testing and they had pushed the terminal in and not corrected the condition.
I did find out what the original problem was and I will post about it tomorrow. The following picture is where the gauge should be normally when the the low speed fan comes on.
This is just a pet peeve of mine and has nothing to do with the repair but here it is. The air filter had obviously been replaced. Why did the installer not clean the dirt out of the air filter box? It takes about what 30 seconds to vacuum out the dirt with a shop vacuum? It just bugs me!
To see part 2 of this repair please click here.
Well, well. My 2004 1.8 Focus started overheating – but only after 50kms or so, and only under load (I drive downhill to work – no prob; uphill home – temp goes up).
Ford Main Dealer supplied and serviced, including full flush about a year ago. So took it in. ‘Sounds like a radiator blockage to me’, says I (because I don’t know anything).
‘We’ll run a diagnostic’, they say, and confirm that it must be the radiator.
This is Western Australia – I’m not messing around. Had a new rad fitted – by a specialist (half the price), so FORD dealer charged me about $100 for the ‘diagnostic’. Two weeks later the water pump started leaking. Had a new pump fitted.
Now spent over $1,000. Still overheats.
Then, just the other day, I thought to myself ‘why can’t I hear the fan kicking in . . ?’
I might add that this is the same dealer who, after servicing the same car under warranty for three years, charged me over $500 to ‘diagnose’ and install a new coil pack “because the spark plugs were unservicable” and blew it up.
Am I impressed?
Is this a blower issue or a temperature control problem?
hi im having trouble with my Bonneville that i cannot turn on my heat or air without bypassing and restarting it… what could it be? i have to turn on the heat put it to 90 and then back to 65 then shut it off then turn it back and then it works… what could it be?
I looked at some wiring diagrams and your 2002 Focus is very different from the 2003 I posted about. If you are comfortable with using a multimeter (and own one), I would suggest buying a wiring diagram from either Mitchell or Alldata. There are links to both at the top of the page. I would be happy to help you work through your problem once you have the needed tool and info.
Hello,
I am having some issues with overheating as well. I have a 2002 ford focus SE 2.0 L Zetec. Neither of my fans will turn on regardless of the A/C being turned on or not. I have pulled and inspected the fan resistor pack and it looks ok. There some green oxidation, and the cage around the resistor is rusted badly, but the resistor and connector seem to be fine. I’m not exactly sure how to test the two relays located at R15 and R16. But the fuses are all fine. Any ideas what my problem might be? Oh, another thing I should mention, my temp gauge will warm up to about halfway (maybe slightly under, but never goes above that. Kind of weird considering the engine gets so hot.