:? :? I can?t find the plug, does anyone know where it is? My 300D is on passenger side front, but can?t find the 300SDL plug. I just changed the glow plugs, but have problem with relay. Until I can get it to the shop, I need to plug it in for the first start of the day. Anyone know where it is?
? Unless a block heater was installed sometime after the car left the assembly line..... you don't have one. It is an option.
Usually they will run to the tow hook cover area if equipped...
I know all about glow plug system so if you want my help, I can tell you how to fix it. To start off with... the glow plugs you replace with... are they the same as the one you took out?
Here's what I know about glow plugs: Beru and Bosch are original and last a good number of years.
But, your car will start on ONE if you have good compression so many can fail and you might not know. Till that last bugger goes.
Monarch plugs are not oringal and don't last as long BUT burn hotter so they're good for older engines.
IF the car has a heater, the plug should be either under the front bumper OR on passenger side of car (open hood and look behind the head light area).
NOTE: SOME cars do not have the heater. (usually only equiped on cars that were being shipped to cold climats). You can order a heater on line if you want.
Glow plug relay is very easy to change. I would just order it online, is shipped. However, it usually is NOT the relay that goes bad.
The way to check is to disconnect one of the glow plug wires and check the voltage from the wire to ground. Then flip the key as if to start the car. You should read 12 volts.
If you do NOT, then disconnect all of the wires to the 5 glow plugs. Then check for voltage (after you turn the key). This is the sure check if it is your relay.
You see if 2 or more glow plugs are BAD, then the relay will NOT work. (The relay is designed such that if there is too much current/draw on the relay, the relay will trip off. It appears the relay is bad but it is doing what it is suppose to.
Mercedes Scot
"Kathy23805" wrote
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