Stevo-M 0 Posted April 18, 2009 Hi guys, whats happening is the water temperature light flashes when the engines just started from cold, and goes out after a while, but If the engines switched off and on again then it stays off. The temp gauge sits at about 90, and the fan comes on and off as it should. Any ideas? Or more to the point, how can i make it stop for the M.O.T. :lol: ? ...disconect the sensor? Cheers Quote Share this post Link to post Share on other sites
Toad 0 Posted April 18, 2009 It flashes to indicate a problem with the level. Is this an issue? Have you got proper coolant in it as pure water confuses the sensor. The sensor or wiring to the sensor could be knackered too... It's not an MOT fail as far as I am aware.... Quote Share this post Link to post Share on other sites
Toad 0 Posted April 18, 2009 Hang on... Having read that again. Do you mean it flashes for 5 seconds and goes out, doesn't come back on again? Because it's supposed to do that.... It's a self test feature in the clocks. Quote Share this post Link to post Share on other sites
Stevo-M 0 Posted April 18, 2009 Hmmm, quite possibly :lol: , 'though i'm sure it's longer than 5 seconds, i'll check it out 8) Thanks for that :) Quote Share this post Link to post Share on other sites
davidwort 0 Posted April 19, 2009 similar problem on mine, doesn't seem to be the temp sensor for the gauge or the header tank/header tank level sensor, both have been swapped, it's either a wiring or gauge issue, haven't had time to swap the gauge over yet, I've a spare to rule that out. It is odd, sometimes I just get a few flashes and then it behaves, or sometimes the gauge raises to max now with the light flashing, it's not overheating though, and as you say, turn the ignition on and off and it resets itself and doesn't repeat??? Quote Share this post Link to post Share on other sites
Stevo-M 0 Posted April 20, 2009 I checked mine today, the light stayed flashing for over 5 minutes :( It could be the cololant though, it's kinda brown... Quote Share this post Link to post Share on other sites
davidwort 0 Posted April 20, 2009 I checked mine today, the light stayed flashing for over 5 minutes :( It could be the cololant though, it's kinda brown... did you try the ignition OFF/ON again trick? Quote Share this post Link to post Share on other sites
Stevo-M 0 Posted April 20, 2009 I had a blast in it today and the light was on for the whole journey, about 5 miles, then i went into a shop for a few minutes and the light stayed off when i started the engine again. It doesn't bother me as the gauge works fine, 'just hope MOT man hasn't got an issue with it! :? Quote Share this post Link to post Share on other sites
vwdeviant 0 Posted April 20, 2009 Checked the level when it's flashing? Could be an air-lock... Quote Share this post Link to post Share on other sites
Supercharged 2 Posted April 20, 2009 Once it triggers it will stay on until the engine is restarted. Use of hard water can cause this so worth trying a new tank and change of coolant but also check the wiring to the sensor. Quote Share this post Link to post Share on other sites
davidwort 0 Posted April 20, 2009 Once it triggers it will stay on until the engine is restarted. Use of hard water can cause this so worth trying a new tank and change of coolant but also check the wiring to the sensor. somtimes yes, sometimes no, I've had mine flash and the gauge rise and then drop of it's own accord, oil temp doesn't change and I loose no coolant and I've never run the engine on anything other than distilled water, def no airlock, it also still does it with a new VAG header tank and when switching the temp sensors around on the side of the head :scratch: I'm down to wiring or the gauge itself, I found a round VDO temp gauge the other day, so might try that before stripping the dash, I assume a short would give a max gauge reading and flashing LED? Quote Share this post Link to post Share on other sites
Toad 0 Posted April 20, 2009 The gauges just pull out of the pod Dave, you only need remove the front and pull it out and swap over to a new one. Did this on the VR. Didn't fix my issue. Then drove off with my wallet on the roof. Quote Share this post Link to post Share on other sites
colinstubbs 0 Posted April 20, 2009 Then drove off with my wallet on the roof. Result!! Quote Share this post Link to post Share on other sites
davidwort 0 Posted April 20, 2009 The gauges just pull out of the pod Dave, you only need remove the front and pull it out and swap over to a new one. Did this on the VR. Didn't fix my issue. Then drove off with my wallet on the roof. cheers mate, will attack the old passat dash I have, I'm sure the temp gauge is the same. :lol: about the wallet, I know it's not funny really, but it's the way you recount things :) reminds me of one morning I drove off to work leaving my rucksack on the drive, wallet, work pass etc in it, fortunately when I realised and drove the 20 miles back again it was still sat on the drive all on it's own :clap: Quote Share this post Link to post Share on other sites
Jim 2 Posted April 21, 2009 WTF? I posted a reply to this thread and now it's gone? Anyway - in short, check the connector plug that attaches to the expansion tank. I was getting the exact same symptoms as you (light flashing from cold, would clear once the car was warm if I restarted the car) and it didn't matter how much coolant was in the bottle / how clean it was. Turned out the pins in the plug that connect to the expansion tank were bent back so it wasn't making a proper connection. It might be, in your case, that the contacts are corroded or something so maybe get in there with some electrical contact cleaner? Quote Share this post Link to post Share on other sites
davidwort 0 Posted April 21, 2009 cheers Jim, think I've peered at the connectors before but never really carefully and not recently, and apologies to Supercharged, it wizzed up the gauge and flashed all the way to work this morning soon after the engine started to warm up. Quote Share this post Link to post Share on other sites
Stevo-M 0 Posted April 21, 2009 I'll check that connection out, 'sounds quite likely. I suppose i should change the coolant as well, as far as i know mud isn't very effective at keeping engines cool! :lol: Thanks for the advice! Quote Share this post Link to post Share on other sites