Hello all

update, now exactly 850 miles from home and still having intermittant electrical problem...

van will die while idling or driving, did so twice today on 45 mile drive... once I coasted, while speedo and guages went offline for about 4-5 seconds, searched for N and a second or two later the guages and speedo came back and I started it while still rolling and continued to drive...

15 miles later, I had to stop and do a check-in at campground, letting engine idle... in 4 minutes the engine died and when tried to start, no gauges... did not wait to see if NO BUS would appear, before shutting off key and sitting a minute... tried to start 2-4 times and finally guages popped back on and it started and drove 5 minutes to final destination...
I was NOT towing, as I had a new found local friend do that for me.

This is not heat related, as the same thing happened to me Saturday morning after driving for about 200 yards at campground speeds... came to stop at T intersection, engine died, NO BUS and I sat there for about 15 minutes before a good soul towed me back to camp site. I put it in Park, got out and thanked him, reached in, turned key and it started right up. DAMN!

1. reman PCM put in Friday with no fix, no change at all in engine run condition
2. I thought I fixed it when I found loose connection at 10 amp fuse marked PCM/fuel pump/ASD (fuse 6) when I merely touched it with engine running and engine died
3. I can recreate problem with engine running by pulling that fuse,,, NO BUS no start
4. fuse box on side of dash has short wires running to it so I cannot turn it around to look for bad connector on rear, but twice when I push-pull on cable bundle near wires coming from fuse 6 the engine will die, but cannot be certain because I cannot reproduce this and cannot find A wire to touch because of short leads to box
5. at idle, the engine will die within 2-10 minutes but usually start again
6. when running at speed, the engine will stumble hard, but then run again fine in a matter of half a second
7. the last thing I did to this van was have fuel pump replaced (preventive) by reputable mechanic end of September... since then I have had the engine stumble very briefly and rarely, but never die on me, or have the no start NO BUS problem... have driven with this condition for about 8500 miles over four month period, but now the NO BUS no start has given me fits for the last 2 1/2 weeks and engine will stumble while at speed (very rarely, maybe once in 2-3 hours of driving) when I do get on the road. NO OBDII codes that I can read nor were any found when I took to dealer 15 days ago.

Now I am looking at replacing ignition switch and possibly dropping fuel tank and looking for bad connection to fuel pump...

Could ignition switch or fuel pump connections give me NO BUS condition?

Anything else I should look at? I have cleaned most every connector I can find and grounds, and fuse box connections in black box (fuseable links and relays) and everything looked fine. Took out and ran engine without instrument cluster. Weather here in FL panhandle has been pretty consistant in low to upper-70's mid-60's at night for two weeks, I see no connection with heat or lack thereof.

Planning on driving this home without towing and seeing how far I can get... will drive it weekend of the 25th to miss most heavy traffic... I-65 from Montgomery AL to southern KY will be the hardest...

 

a funky operating relay?

I would have to check the diagrams for that...

 

sounds like you have a bad cluster cpu..... or a bad ground.....


why so many threads on this?

 

No buss is a communication issue with the pcm. Since you moved some wires around and it died it would try this again to see if you can replicate it. If so it must be in the wiring somewhere.

 

The new PCM could be a bum one or the new crank sensor could be too.

 

A bad crank or cam sensor would not give you a no buss.

 

Any luck yet?

 

Apparently a short in the crank sensor can cause a no bus condition.


I'm not sure about the ignition switch. Nobody else responded to that question and I'm sure you're still wondering...

 

When my ignition switch was bad, it affected the power windows and radio. They both would either blow the fuse or trip the circuit breaker. Or, they would just stop working or work erratically.

I did not get a NO BUS when my ignition switch went bad.

 

suspect asd/fuelpump relay or connections there of