Hard wiring preheater plugs

gunslinger

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Hi
I would like to wire my preheater plugs to a switch on the dash ,thus avoiding the timer relay box.
Now I would have thought that running a cable from the battery to a switch and from the switch to the first plug would do the job.

However having tried that,it does not seem to work.
I have done exactly this on other vehicles but on my 250td the heaters are not working,but they were fine before the timer packed up.

Any advice appreciated

Mike
 

5pares

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Suffolk
Your Mercedes
E320cdi
Surely replacing the glow plug relay would be easier,but they should work if they are feed 12v,they will draw alot of current tho so the wiring and switch will have to be up to it.
 

Number_Cruncher

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Your Mercedes
1995 W124 E300D TE
>>thus avoiding the timer relay box.

Why do this? The timer relay works very well in its standard form.
 

meanie

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I think that you'll need to run a 'hard wire' to each of the plugs,or link them together.The relay supplies voltage to each plug individually.
 

wireman

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lancashire
Your Mercedes
nice 201 2.5D 1993 & very nice 129 SL500 1994
You will need a switch that can handle 100 Amperes for make and break that will fit inside/behind your dash , I have no idea where one of those will come from or wher there is space for the switch and cables, More to the point over doing it with the heaters will shorten the life of the plugs or flatten the batery in no time.

The standard relay provides accurately metered supplies to the plugs in accordance with the engines requirements for both pre start glow and post start glow operation of the plugs as required by the engine and climate. The times for these periods are determined by ambient and engine temp sensors.

In short by the time you have re-enginerred the wiring (in very fat cables) and found the unobtianium switch the bill will be more than the price of a proper relay with its internal timers, temperature sensors and circuit protection, which will fix the heaters properly in little time.
 
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