Check engine light

[RKleypas]

03 CTD with a 48re transmission. I'm driving down the highway the other night and check engine light flashes. Few minutes later, it flashes again. Next day it flashes again, and that's the last I've seen of it. Two questions: Does the maintenance schedule cause light to flash when it's time to change the oil? I have 4000 miles and I'm on sched. B. Also, does the grid heater pulsing off and on pull enough amps that the computer could be detecting that as an altenator failure? It was maybe 40 F here in Houston, but I know the heater had pulsed some the night before (35 F). Anyone else with anything similar? Engine is running fine.

 

[rbattelle]

It might just be an electrical bug. If a code is detected, the MIL light should remain on, rather than blink. The grid heaters won't cause an alternator code.



Early in 2003 we had a "check gauges" light that would blink like that periodically. It was a bug, fixed by an ECM reflash. Perhaps something like that is happening?

 

[RKleypas]

I appreciate your response. I can't remember, but the truck only has a "check gauges" light correct? If it has both, I don't remember which was flashing. Anyway, if I have no more recurrences, should I still get the ECM reflashed? Thanks

 

[COBRAJET]

The trucks have both a "check guages" light and a "check engine light". There have been problems with some trucks and the "check guages" light. The light will flicker on and off a few times than stay off. This is fixed by the dealer reflashing.



The "check engine" light is totally different and is the same as a malfunction indicator or a service engine light. None of the three pertain to any type of maintanace. This light comes on when the computer senses a problem with the engine management system. If the light flashes several times than stays on you should get to the dealer. If it comes on and off something is triggering it... there are literally hundreds of things that could bring the light on. As long as it goes back off it is likely not a big deal. If it is on more than off the computer should record the problem. You can cycle your ignition key several times to the on position without starting the truck and a saved code will be displayed on the odometer screen. This code can be interpreted on this site or at your dealer. There are several websites which lists most OBDII codes as well..... just type OBDII codes on a search engine... . CJ

 

[SteveH]

Mine did the same thing on a 4000k trip last week pulling a trailer. Seems like if the trailer isn't grounded separately through the wiring harness, it will intermittently trigger the check engine warning light. It only stays on for about 1 second, not long enough for the code to get caught by the computer when they try to access the trouble codes. If you were pulling a trailer and its grounding depended on the ball or hitch, especially if you greased the ball, this may be your problem.

Steve H.

 

[RKleypas]

Thanks guys; all good info. I had been pulling a trailer earlier that day and shootin' it with my buddy, so it may have flashed without me noticing. I grounded the white wire on the trailer straight to the frame rather than through the ball though. I haven't seen the light since though, so I think it must be the instrument cluster computer bug.

 

[BrittonTurner]

Originally posted by RKleypas

Thanks guys; all good info. I had been pulling a trailer earlier that day and shootin' it with my buddy, so it may have flashed without me noticing. I grounded the white wire on the trailer straight to the frame rather than through the ball though. I haven't seen the light since though, so I think it must be the instrument cluster computer bug.

same thing happend to me a few weeks ago. the "check gauges" light came on for just a second and went off. did this a couple of times and haven't seen it again. just a bug i guess.



britt