Flashing lights!!

An alchemy of sparks, copper wire and earth

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Wearside wanderer
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Flashing lights!!

Post by Wearside wanderer »

so I have developed a couple of new unwanted disco lights on the dashboard, firstly the water Coolant, however I know it’s all topped up etc so I’m hoping that’s a lose connection.
More concerning is the oil light, again it’s fresh oil and recently drained. It tends to come and go but it makes a screeching noise and it’s not constant, basically is this another lose connection or something more sinister.
Unfortunately it won’t let me link a video, any help advice appreciated.
1989 T25 High Top 1.9 petrol/LPG
Hamish the Cairn Terrier mobile

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AngeloEvs
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Re: Flashing lights!!

Post by AngeloEvs »

Check the condition of the wiring and the connectors to both oil pressure switches, one is under the push rod tubes and the other near the lower pulley. If ok it maybe a faulty oil pressure switch or a problem at the dash . The oil pressure switches behave differently with respect to the connection they make with chassis earth. With the correct pressure, the one under the push rod tubes will open and the one near the pulley will close. To test wether one or more of the switches is the problem you could simply remove the connection to the one under the pushrod tubes and disconnect the one near the pulley and connect it to chassis earth using a length of wire.

The coolant LED problem can be caused by a number of faults if the coolant is at the correct level in the header tank.

First, remove module 43 ( or 42) which is your fuse box and looks like a relay - see if this clears the fault. If yes, the fault is in the coolant level circuit or the module may be faulty. Check the condition of wires and the connectors that go to the coolant level sensor mounted at the top of the header tank. Also trace the wires as one goes to chassis earth (usually by the coil) and make sure it is sound and connected.

If with module 43 removed the temp gauge led still flashes after the self test and the temp gauge reads normal temperature then it may be a problem with the gauge, or the securing nuts are loose or the 14 pin multiconnector at the dash may need inspecting.
1987 DG Karisma LPG with remodelled interior

Wearside wanderer
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Location: Sunderland

Re: Flashing lights!!

Post by Wearside wanderer »

Think this is going to above my knowledge level.

Thanks for the help 👍
1989 T25 High Top 1.9 petrol/LPG
Hamish the Cairn Terrier mobile

Dream-Drive
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Re: Flashing lights!!

Post by Dream-Drive »

Greetings. We have a 1985 DF, 20,000 miles from new. Yup, it's still brand new. BUT, we have a persistent red lamp flashing under the temperature needle. Sometime it's off for a while, but if you re-start, on it will come. New Level sensor, blocks cleaned in Engine Bay Black Box, Earth's redone, so engine, under coil, replaced temperature sendor... we move up front. Fuse box out (first time since build), up to Relay Holder 43. Pull that, mint, replaced it, light continues to pester. Re-do Earth Crown. Pull dash out, check connectors & the nut in the middle. Hey Presto, it's still on!..... Two question, how can I kill that red light, cause I really don't want to touch is historic foil?...... Any ideas please how to kill the flashing light, or do I need to take the plunge and replace the temerature gauge. Yes, I did check the earthing on the dash too. So sensitive, but un-reliable!....... Thanks in advance. 

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AngeloEvs
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Re: Flashing lights!!

Post by AngeloEvs »

Can you clarify if removing the module 43 stopped the temp gauge LED from flashing? If yes then the temp gauge is not the problem. The fault is in the coolant level circuit which is activating module 43 and this triggers the LED. Most likely you have an intermittent connection from the level sensor to the module 43. You will need to do continuity tests - since the led is permanently flashing you might as well remove module 43 until the cause is identified.
1987 DG Karisma LPG with remodelled interior

SurfT25
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Re: Flashing lights!!

Post by SurfT25 »

My bus had continuing flashing light when I got it.
Turned out to be the wire ribbon in the dash was kaput.
The garage that tried to fix the problem had put wires with connections through the ribbon to try and fix problem :shock:
Image
This did not work and the screw ends could be seen in the speedometer casing :evil:
On day out at Busfest 2019 I got a damaged casing but intact vertical connection ribbon.
With a bit of patient's, eventually, it goes to show that two minus's do make a plus 8) .
So do check your ribbon.
Good luck
Last edited by SurfT25 on 12 Sep 2021, 13:09, edited 1 time in total.
Prepare for the worst but hope for the best

1984 1.9 DG WBX Autohomes hightop

Dream-Drive
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Re: Flashing lights!!

Post by Dream-Drive »

AngeloEvs wrote: 09 Sep 2021, 17:42 Can you clarify if removing the module 43 stopped the temp gauge LED from flashing? If yes then the temp gauge is not the problem. The fault is in the coolant level circuit which is activating module 43 and this triggers the LED. Most likely you have an intermittent connection from the level sensor to the module 43. You will need to do continuity tests - since the led is permanently flashing you might as well remove module 43 until the cause is identified.

Yes, I pulled the module 43, light still flashing, even after a restart. Replaced 43, same results. I have peaked behind this virgin dash, checked the centre nut, but didn't check the two side ones (all three are temperature gauge). I'll try that as a last resort (using switch cleaner) before having to presumable replace the temperature gauge complete. Where does one buy one of those NOS? (fits in top part of pod, fuel on bottom). Any other ideas before being SO radical? Could it be the voltage reduction bit on the back of the cluster?..... Thank you in advance.... 

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AngeloEvs
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Re: Flashing lights!!

Post by AngeloEvs »

If the temperature gauge pointer is in the normal position, all three securing nuts are tight and the LED flashes continually with module 43 removed then the dash needs to be removed and bench tested. The voltage regulator provides 10v to the gauges and this also needs to be checked and that the voltage is stable. Although reliable, the temperature gauge can develop a fault due to a failed capacitor which needs to be replaced and requires the temp gauge to be removed. Sent you a PM.
1987 DG Karisma LPG with remodelled interior

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