Lx665 preheat error

[pat44]

Hello all. I have an lx665 that won't preheat. It starts the countdown and you can see how many seconds but after a second it shows error f03. When I turn the key you can hear the relay click. It starts operates fine if it's warm enough otherwise.

 

[Shanmar]

f03 is for the preheat relay, as you may have guessed. Need to troubleshoot that circuit. If it is that relay clicking, put a meter/test light on it and make sure it is sending power out to the glow plugs. That's where I'd start.

 

[pat44]

I will check when I can find someone to sit in the seat and turn the key tomorrow

 

[pat44]

It is not sending power to the glow plugs. Suspected the relay or glow plugs at first so replaced them and the relay but still no power.

 

[Shanmar]

Check if power getting to relay, both from main power supply and the switching power signal. Could do a continuity test across relay to verify it's closing when it should be.

 

[pat44]

Only getting power from main power supply

 

[Shanmar]

Looking at an LS160/170 wiring diagram (very little difference vs the LX series), looks like the trigger signal for the relay comes in on a Light blue/yellow wire coming from the #2 pin of the larger connector on the back of the board in the dash. Suggest checking continuity through that wire/corrosion at the ends, etc. I'd also check/clean grounds and battery connections just to be sure.

 

[pat44]

Thank you. I will hopefully get a chance to do this tomorrow.

 

[jdof]

Did you get it figured out? Mine is doing the same thing

 

[pat44]

No, unfortunately I haven't been able to look at it lately.

 

[jerry]

No, unfortunately I haven't been able to look at it lately.

When put the service/run switch in service and depress the button beside the switch do the glow plugs activate?

T

 

[pat44]

It doesn't have a button to preheat. It's the newer gold line display.

 

[jerry]

The button switch on mine is beside the service/run switch and manually controls the preheat relay when in service.

 

[Lucy Green]

Did you get it figured out? I want to know the reason

 

[pat44]

No, I havent been able to do much with it and it looks like I wont be able to dig into it more for a while. Sorry