No start

[Robert Mielenz]

1997 Patriot with a 3126 engine. Was running just fine, shut it down and when I tried to restart the next day it wouldn't start. I noticed the engine pre-heat light did not come on, Tried two or three times no start. Turned key on and pre-heat light came on and engine started. Next day no pre-heat and the engine refused to start. the temperature is in the 50's and it normally starts just fine without waiting for the pre-heat cycle. Any thoughts, electrical problems?? etc.

[Dave Atherton]

Robert, check electrical power at relay going to the engine ECM . Follow red wire to pin 40 lower
Left corner to ECM J-1 connector that feeds data to dash gauges . That red wire needs power for you to start. Dave Atherton Retired Cat Mechanic

[Dave Atherton]

Robert, another area no start , location air intake heater bolted to the engine head with what
Is a relay with 2 wires is called timer relay bad connections. Next close by is a another relay
That operates the intake heater again bad or dirty connections ( note has a hot wire on top end
and ground on other end lower side end . My suggestion first after more info look at this area
first and the relay that connects power to intake heater. If timer relay is not working or bad wires
you can take out of system and install later ) the intake heater will prevent start and is controlled off engine ECM. Can give more detail information in AM.off Cat SIS if you cannot get running.
Dave Atherton Retired Cat Mechanic

[Robert Mielenz]

Thanks Dave  will get on it tomorrow

[Robert Mielenz]

After some expert advice from Dave Atherton, the problem is solved. A bad power wire to the ECM. Re did the wire and everything is working again. Its almost always easy after you diagnose the problem. Finding the problem, however is not always easy.  Thanks Dave.