starter issues. 1999 - 2003 7.3L Power Stroke Diesel - Question regarding wiring for glow plug relay - Hey folks, I have recently picked up a 2000 f250 7.3 and am currently checking over the glow plug system. Resistance on all glow plugs were in tolerance. Glow plug relay would not send power to glow plugs. My question is this. This is a Ford CMAX that needed 2 Injectors removed. Unfortunately for me to install my equipment onto the engine, the drivers side engine had to have the bolts removed from the chassis and then the engine was slid forward. The WTS light is not tied to the glow plugs. If the WTS light is going on and off with the cycling, that's just further indication that it's a main power issue. 1995 FORD F350 7.3 POWERSTROKE ABOVE 32 DEGREES GLOW PLUG LIGHT COMES ON AND THEY WORK CAN SEE VOLTAGE GAUGE CLICKING BACK AND FORTH. FOC Supporters. 14.3k. Name: Unofix. Ford Model: Focus 2.0D Titanium X auto - Estate. Ford Year: 2019. UK/Ireland Location: Durham. Posted June 14. There is zero chance of the glow plugs being active in the current weather. Even when they are on in cold temperatures the supply is on for less than a minute. The glow plug relay is commanded on for a length of time up to 120 seconds by the PCM, based primarily on engine oil temp and barometric pressure. It won't be commanded on at all if the EOT is 131° F or higher. The wait to start indicator lamp on the dash is controlled separately by the PCM. Thanks for sharing. 20 Years of ownership of a 99 7.3. 1999 - 2003 7.3L Power Stroke Diesel - Stancor 586-902 Glow plug relay - Anyone running the Stancor 586-902 GPR? Mine stock relay went bad and I replaced it and it’s not powering again and we think it’s bad (again) so I saw people were running the Stancor one. Who’s using and how’s it working for you. When you Crank the Starter + Voltages goes through the White Wire to the Violet one and turns the Glow Plug Relay Off. Terminal 50 input is to interrupt the glow cycle following engine start. Terminal 15) Run start input. rd/bk (Black) ignition switch from the starter. Terminal 31) Ground. br (Brown)ground. Ford Focus red cog with red exclamation mark warning light Powertrain warning light. The red cog with a red exclamation mark warning light signifies a fault with the powertrain. Typically, the usual reason is a fault with the faulty glow plug relay or a fault with the glow plugs. Diagnostics will specify the exact fault. Vehicle is safe to drive. 4wHER.