No Response key in start position

[CElmore]

2007 5. 9 larimne all stock. i got in my truck and tried to start my truck and it acted like the batteries were dead. i jumped my truck and went and got two new gel batteries it then started fine. the next day i tried to start it and nothing happened. the lights in my dash all came on and the radio played but no response to even think i had turned the key to the start position at all. the wait to start symbol never came on even when it was only 30 F outside. (usually does with temps that low). i got a boost charger hooked it my battery and it started right up. i pulled the truck in the shop to see what may have cause the initial problem. after shutting the truck off i tested the batteries, they were good. the key was turned to on and the wire to the intake heater relay was quite hot. i then noticed the intake heater was smoking and i quickly shut the key off and discouncted the battery. a service tech tested the system and said the relay was shot and the heater had a short causing it to burn up. i discounected the heaters power wire and replaced the relay. now the truck when i turn the key to start does nothing but ussal lamp test of the gauges and all but no engine response. the check engine light also flashes rapidly. is this because the ecm does detect resistence from the relay. help please with anything u can. ask away i will answer as best i can. thanks

 

[JFought]

you need to load test the batteries , with them not attached to each other
then the result will point to whats next

 

[rscurtis]

I doubt the heater had a short- it basically is a 190 amp short circuit. It was probably energized too long by a possible relay problem. This could also be just a symptom of the real problem- whenever it is discovered.

 

[CElmore]

thanks for the advise com to find out the intake heater relay was stuck open and when the key was left on it just kept the heater on and made it short out. i guess the reason it didn't start is because the computer didn't sense a resistance in the current. thanks