I have some weird issues on my truck that come and go, First off it is a 2000 CTD, 2 wd, Automatic, 218K on the clock.

I was going down the highway one evening as it was getting dusk, turned on the headlights...and the engine shut down wth?

Coasted to side and tried restart no go. Turned off headlight switch and restarted fine, then found out I had no A/C or  heater blower fan.

Little ways down the road the fan came back on?. Weird thing is when its cool out its fine, real hot out 90's and no go. I am going to check all the battery connections and grounds this weekend, Will check codes, there was a code no comm between ECM and Injector pump I think it was? Thinking there is a corroded connection or a week connection somewhere, First place to look? any help is appreciated, Thx

Check the ECM connection and the vp connector also. Clean them up and put a little dielectric grease on them. My VP connection tried to work itself loose not long ago. The little slide that holds it in place had worked itself loose. I had no issues just noticed it one day while under the hood. 

 

Does the truck shut down every time you turn on the lights?

Also what type of mods or electrical "fixes" have been done.  I would be suspicions of corrosion, especially on poorly spliced wires.

Dripley;

I will check these points again but have cleaned and greased both you mention.

When it is hot out, most of the time if the check engine lt comes on or the blower does not come on I will have the shut down issue when I turn the H-light switch to the on position. This am it was cool out, so no issues..

Hawkez;

Have ran an extra ground prior to the ECM, and the shielding for the alternator, and a bully dog programmer, other than that she is stock.

I would like to see electrical diagrahms for the ECM, Fuseblock area, Headlights ect. I know they are on this site but I am not as Computer literate as soom and cant seem to find them, could someone, Mike? maybe post the links here for me please. that would be a great help for the upcoming weekend working on the truck..

Thx   Randy

Why the extra grounds?  Did you splice in the ECM's wiring?  Also, you may want to throw a volt meter on the alternator and check for AC voltage.  At the top of the site's page, you should see the ARTICLES tab.  Click on that and you should be able to navigate to the different sections of information.

The wiring diagrams are in the articles section. Go to articles, 2nd gen, engine, eletcrical in that order and you can choose your year vehicle. 

The shielding for the alternator is masking stray ac voltage. The problem is still there and bad on the electronics. The article mentioned above covers it pretty well.

Thx for the help, I will dig into it over the weekend

was a code no comm between ECM and Injector pump I think it was?  Check the big connection on firewall. The one with the white bale, it needs to be like this.