Technical Panda Overheating

[Frank B]

My sons 55 reg Panda 1.2 intermittantly overheats, its been in the garage and everyting checked is OK, hoses, radiator , fans and it won't overheat for them. They changed the thermostat as a precaution but hasn't solved it.

It only seems to happen when driving in heavy traffic when the aircon is turned on.

Suggestions ?

Thanks

 

[A3jeroen]

Did they check for dirt between the aircocondensor and the radiator?
Does the fan come on with the AC?

gr J

 

[koalar]

Fans not coming on by the sounds of it

 

[koalar]

Seem to remember that they run at two speeds. Cant seem to find any info on it. Did I mix it up with one of my other cars ?


I would have guessed the second speed hasn't been checked. But could be miles out?

 

[Eklipze3k]

If it does it in heavy traffic it really ought to do it if left long enough just sitting with the engine running and AC on, I suspect the garage are not letting it heat up enough.

When it happens, turn AC off put the interior blowers on full and full heat (open the windows if needs be). Does the temperature start to drop? If so, I agree that it's a fan issue.

 

[Frank B]

Should the fan come on whenevere the aircon is on ?

 

[irc]

Have seen similar symptoms in the past where the second fan speed did not work, although the lower speed did.
Only overheated when aircon was on in traffic on hot days.
Can't remember exactly what the original cause was, but turned out the fan unit itself had a fault, and replacement fan, relay and fuse must have fixed it, as I found the parts invoice.
(I usually write a note of the problem on the invoice, so maybe someone else fitted the parts this time)

 

[Tizzywizzy1uk]

Sounds like air in the pipes, or thermostat. I'd chech that all the pipes are getting hot and check the two bleed points. I had a thermostat replacement once and had to change it as it was brand new and defective.

 

[multipete]

Should the fan come on whenevere the aircon is on ?

Fans should come on when air con is on in standing traffic,that's normal. How high does the temp gauge go when it over heats?

 

[Frank B]

It gets hot enough to start losing its water. I'll have to let it idle to bring the fans on then turn on the air can to see if a second fan comes on. I only get to see the car once in a while which makes diagnosis difficult, I didn't know there was a second fan

 

[Eklipze3k]

It's not a 2nd fan, the fan has 2 speeds, so when irc says "second fan speed" they don't mean another fan, they mean the radiator fan spins faster or slower depending on load and heat.

 

[irc]

It's not a 2nd fan, the fan has 2 speeds, so when irc says "second fan speed" they don't mean another fan, they mean the radiator fan spins faster or slower depending on load and heat.

Yep. Sorry, should have made that clearer. One fan with two speeds on aircon models (and maybe others too), although the UK 1.1 active only has a single speed fan.
Non-UK cars may be different.

 

[koalar]

Thought I better check I hadn't sent everybody up the garden path.


Yes aircon Pandas use two speeds for the fan


The fan is the just a standard fan.


Speed one and two are completely separate circuits going to the same fan

Speed one goes through a resistor via relay 6 and fuse 6 (must be working)
Speed two goes direct via relay 7 and fuse 7(needs checking)

The engine management senses the refrigerant pressure sensor and coolant temperature sensor to make a decision which circuit to switch on.

 

[DuncanHill]

This might sound a bit basic, but my old Panda 1.2 8v used to overboil in crawling traffic, especially on hot days. I used to put the heater on full go to stop it. After a service with timing belt and water pump change, and flushed rad, never happened again.

 

[Frank B]

Fuses OK, will now replace the relays

 

[Frank B]

Re: Panda Overheating sorted

Sorted hopefully. Auto electrician gave it a thorough check, turned out the fan had an intermittant fault and has replaced it. The relay was also showing signs of wear so that has also been replaced

Thanks for all suggestions