E46 engine code fault

Deleted User 234324 · 24 Jul 2010 at 15:29

Lo folks,

Just got my diagnostic thingy this morning, plugged it in and the only fault code shown is P1620 Cooling Control Circuit Signal High.

Im going to assume its something to do with thermostat, should i be worried ?

Duke · 24 Jul 2010 at 15:32

Sounds like it - http://forum.e46fanatics.com/showthread.php?t=520978

Maz · 24 Jul 2010 at 15:44

Nothing to be worried about, as the Thermostat doesn't fail completely.

It won't get upto normal running temp and the car will run rich, ok for a little while but not recommended for ever!

Thermostat replacement isn't too difficult (assuming you've for a 6 cylinder) I've done three of them and it takes an hour max.

Never done it on a 4 cylinder though.

[TW]Fox · 24 Jul 2010 at 15:54

How long does the car take to get up to temperature, and does it ever move off centre on the guage once it has done so?

Lashout_UK · 24 Jul 2010 at 16:04

Maz said:
Nothing to be worried about, as the Thermostat doesn't fail completely.
.

They can do though

If it fails in the closed position it can lead to prompt overheating and all kinds of trouble if you're not lucky enough to notice it

Maz · 24 Jul 2010 at 16:05

Lashout_UK said:
They can do though If it fails in the closed position it can lead to prompt overheating and all kinds of trouble if you're not lucky enough to notice it

Over heating on a BMW would throw all sorts of disco lights on at the dash followed by rad cap steaming or blowing off!

paradigm · 24 Jul 2010 at 16:15

Maz said:
Over heating on a BMW would throw all sorts of disco lights on at the dash followed by rad cap steaming or blowing off!

Or not.

[TW]Fox · 24 Jul 2010 at 16:24

Maz said:
Over heating on a BMW would throw all sorts of disco lights on at the dash followed by rad cap steaming or blowing off!

It would throw a single red light on the temperature gauge and thats it.

Deleted User 234324 · 24 Jul 2010 at 16:29

Car takes a matter of minutes to head up from cold, never budges past centre even after a 200 mile trip up the m5.

And yeah it is a 6cyl engine.

InvaderGIR · 24 Jul 2010 at 17:20

[TW]Fox;17011966 said:
It would throw a single red light on the temperature gauge and thats it.

This man is right.

Maz · 24 Jul 2010 at 22:45

Temp guage would be bouncing into the red, eml light would come on, battery light would come on when engine dies.

[TW]Fox · 24 Jul 2010 at 22:56

Maz said:
Temp guage would be bouncing into the red,

It would move into the red, and a red light would go on. As I said.

battery light would come on when engine dies.

If the engine has physically cut out due to overheating then it's all a bit late really isnt it?!

Maz · 24 Jul 2010 at 23:09

[TW]Fox;17014215 said:
It would move into the red, and a red light would go on. As I said.

If the engine has physically cut out due to overheating then it's all a bit late really isnt it?!

Like I'm going even argue with you about the sequence of lights due to overheating. Sad sad sad.

Anyway you win - walking encyclopaedia of BMW facts.

Suppose it beats train spotting or do you still do that?

[TW]Fox · 24 Jul 2010 at 23:12

Maz said:
Like I'm going even argue with you about the sequence of lights due to overheating. Sad sad sad.

So you dont think the battery light because the engine has stalled is a bit late to be worrying about overheating then?

Anyway you win - walking encyclopaedia of BMW facts.

Actually I've experienced a fun and exciting wallet busting BMW coolant system explosion which has meant I've kept a keen eye on this sort of thing.

Suppose it beats train spotting or do you still do that?

Ah excellent, we've moved onto personal insults? Do I get to have a go as well?

I, like Lashout and possibly paradigm in this thread, feel its important that the OP knows that if there is an overheating issue (Which I dont think there is on his car) then it can all go wrong very quickly with little warning. As you will know, the BMW temperature guage is damped. It is not a direct representation of the engine temperature. It remains dead centre provided the temperature of the engine is within a specified range. This means that minor fluctuations in engine temperature wont register on the guage - onyl once the temperature has exceeding the range of values will the guage moves. This means the engine is already on its way to overheating when the guage begins to move - you need to notice it and stop the car ASAP.

You don't get a disco of flashing lights to give you loads of advance warning, and if your battery light of all things has come on, then its probably too late.

If you think clarifying this in a thread about fault codes is 'sad sad sad' then you are free not to participate.

PeterNem · 24 Jul 2010 at 23:20

Maz said:
Like I'm going even argue with you about the sequence of lights due to overheating. Sad sad sad.

If it's so sad, why did you enter a thread about BMW fault codes? Seriously, if you have nothing to add other than some spurious rubbish, why bother?

PMKeates · 24 Jul 2010 at 23:26

I remember the time my BMW coolant system exploded.

I was sat there with the car at idle for a few minutes. I noticed the temperature gauge move a little, no more than 1/8th. I switched the car off.

Five seconds later I felt and heard a powerful "bang". My header tank ruptured and the radiator buckled, showering the exhaust manifold with coolant and creating a huge amount of steam! I got out the car thinking it was on fire!

Not a single warning light. Nothing more than a needle twitch...

Maz · 24 Jul 2010 at 23:32

PeterNem said:
If it's so sad, why did you enter a thread about BMW fault codes? Seriously, if you have nothing to add other than some spurious rubbish, why bother?

See post 3#.

More helpful than your unhelpful post criticising me because I questioned the over analysis by one of your BMW buddies.

PeterNem · 24 Jul 2010 at 23:38

Over analysis? He was correcting a complete factual inaccuracy.

Your posts numbers 6 and 11 state as fact something which several of us in this thread know through experience to not (at least not always) be the case. Still, you're "in the trade", I forget you all think you know everything.

hurfdurf · 24 Jul 2010 at 23:43

Maz said:
Like I'm going even argue with you about the sequence of lights due to overheating. Sad sad sad.

Anyway you win - walking encyclopaedia of BMW facts.

Suppose it beats train spotting or do you still do that?

This right here is a pathetic post and should be used to demonstrate exactly how not to post in Motors. I would be pretty embarrassed if I were you right now Maz.

Maz · 24 Jul 2010 at 23:48

PeterNem said:
Over analysis? He was correcting a complete factual inaccuracy.

Your posts numbers 6 and 11 state as fact something which several of us in this thread know through experience to not (at least not always) be the case. Still, you're "in the trade", I forget you all think you know everything.

There is no reference to any to my occupation, only to the fact I've replaced thermostats 3 times.

Once on a 528i I owned, on a 325i Cab I owned and I did the same job on an Alpina B3 that I owned.

I've owned a number of 4 cylinder BMWs and I've never had to replace a Thermostat in them - must be more of a common problem on 6 Cyl models.