Service engine soon,, light and error code

[2000Ford7.3]

Ive had my 2000 F250 5-speed 2wd, for two years now,
stock, no chips,,,
this last winter i was in and out of the hospital, and the batteries went dead,
sat there for two months, DOA,,
i disconnected them a few weeks ago, then 5 days ago i bought new battery's
cleaned the posts, and reconnected everything,
,
went to start the truck, and it took 10 turns to start, drove it, and saw the "service engine soon" light on
went back to the house, freaked out,
started and shut off a few times,
took 4-5 spins to get running,
normally starts on the second/third spin,
,
drove to a diesel shop, this morning, (seems longer to start, dead cold than before), and he put it on the code-reader,
I did notice these things,

since ive had the truck i dont ever remember seeing the "service engine soon" light ever being on, when i just turn the key on and wait for the plugs to warm up,,
now the "service engine soon" light is on with just the key turned on,not running as i wait for the glo-plug light to go off, to start,

WHY?

the service engine light is NOT ON, now, when the engine is running,

the mechanic got this code, P0603
and is telling me i need a new main-brain-computer,
(how much and how deep is that going to hurt me)

he cleared the code,
and the light "service-engine-soon" still comes on, while i wait, for the glo-plugs to warm up, and goes out when the truck is running,

anybody who can help me, would be doing me a big favor as im disabled and have very little funds,
this truck hauls my home around,,permanent RVer,,
150,000 miles on it, and i love my truck,

thank you
jp

[NoRalPh]

No, no, no The P0603 is just a result of having the batteries dead or disconnected from the computer - no sweat, just ignore it...

Anytime you have a light on and the code reader comes back without codes it's because you're using the wrong kind of reader. Our trucks are Not, strictly, OBD-II and generic OBD-II reader don't work well. Any professional shop should be able to pull codes for you though, are you saying the light came back on and you're not seeing a code present?

[2000Ford7.3]

Originally Posted by NoRalPh

No, no, no The P0603 is just a result of having the batteries dead or disconnected from the computer - no sweat, just ignore it...

Anytime you have a light on and the code reader comes back without codes it's because you're using the wrong kind of reader. Our trucks are Not, strictly, OBD-II and generic OBD-II reader don't work well. Any professional shop should be able to pull codes for you though, are you saying the light came back on and you're not seeing a code present?

he is a diesel shop with the expensive code reader,
the light comes on when i turn the key on but I wait to start, engine NOT running,
I see the light,,service engine soon,,

when i start the truck,and drive,, after waiting for my idiot glow-plug light to go out,,lol
i no longer see the "service engine soon" light,,

he hooked up his tester/computer and told me he got a P0603 code and i had to buy a new main-computer for the truck,

batteries are brand new, cables cleaned and good,,

is it normal,
for the "service engine soon" light to come on,,,when the key is on, waiting for the glow-plug light to go off,,
BEFORE starting the motor,,,then go out after motor is running???

truck runs normal, no skips shudders or shakes,,,still takes off like a bullet when i punch it,
but seems to take longer to start up,,more turns before it fires up,

john

thank you for helping me out,

[NoRalPh]

I don't think you have anything to worry about then (other than finding another "diesel shop" to go to)

[2000Ford7.3]

Originally Posted by NoRalPh

I don't think you have anything to worry about then (other than finding another "diesel shop" to go to)

so the service engine soon light coming on in the beginning is ok?
i dont ever remember seeing it before,,lol,,before the start of engine,

and thank you for saving me alot of money,,

[Druknsailor]

All of your “Idiot” lights should come on with the key on engine not running. That’s how you know if your Idiot lights are burnt out or not sort of like a light test. It’s when they stay on with the engine running that there are issues.

[2000Ford7.3]

Originally Posted by Druknsailor

All of your “Idiot” lights should come on with the key on engine not running. That’s how you know if your Idiot lights are burnt out or not sort of like a light test. It’s when they stay on with the engine running that there are issues.

OK, cool, thank you,,
for answering my questions and saving me alot of cash,,

[Turbostang500]

I was gonna say the same thing.

It is just a bulb check. Nothing more.