| Author | Message | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 753 Registered: 10-2004 Posted From: 75.201.7.0 Rating: N/A |
Well I hope I@n doesn't mind me borrowing his heading but it fit my needs better than his at the moment! You see, our great Prevost left us stranded AGAIN! This time it was NOT in the driveway of our home but a 1/2 mile down from where we live, thank goodness for that! I was able to get it started and back it up to a side street and turn it around and pull back into my driveway without any further incident. PROBLEM? I couldn't begin to tell you other than it's the same BS electronic problem I had before the last 3 small trips I took without ANY problem! Check engine light, then stop engine light and then of course SHUT DOWN right there wherever your at! It doesn't care! Anyway, I hooked up my pro-link 9000 and began my troubleshooting! Code 16 is what it says which is low coolant module high voltage! Well the first thing I think, is my batteries are new and the system is getting too much voltage! Wrong, so I get out my 3 inch thick DDEC II troubleshooting guide that takes you step by step to find and eliminate the problem and then erase the code/s! Yea right! Easier said than done! We got to step 3 of 30 and hit a stone wall. Well, not really. It just says that if this doesn't correct the problem by now, start over! Nothing we did corrected anything! Made a call to my friend Dan who lost his legs in a bus crash who by the way is doing really good, (another story) and he is a whiz at this stuff! He listened to my troubleshooting woes and he said it sounds like something simpler than what the book makes it out to be! Told me to disconnect all connections and clean them good and re-connect everything. He also said to check the sensor wires. They don't get oxidized but something else that caused them to not connect good. AHHH, here is where I was sure the problem was because the signal wire going to the sensor was a wee but loose! Not a lot just a tiny bit! I cleaned it and reinstalled that and the ground wire! Now I'm ready to go! Did I mention I was to pick the band up for a trip to Yee-Haw Junction for a bluegrass festival? Guess what? They went without me! Anyway, the long story short is, the wee bit loose wire was NOT the culprit! The dang bus still has this gremlin and so it sits, in the driveway, getting closer to that can of lead free each time this happens! Thanks for reading! I had to vent on someone and it might as well been ya'll! By the way, the neighbor must have felt bad for Susan and I because he brought us over a whole slab of ribs! The town had it's annual pig fest today! Dinner sure was good at least and now that it's over, it's time to ponder over this ELECTRONIC POS... One thing Dan did tell me was that I could take my pro-link 9000 and dis-able the auto shut down feature as long as I constantly watched my gauges and made sure all was good while driving! To me, this might be the way to go! Anyone else ever hear of doing this? Ace | ||
| Jerry Liebler (Jerry_liebler)
Registered Member Username: Jerry_liebler Post Number: 326 Registered: 3-2005 Posted From: 71.31.2.17 Rating: N/A |
Ace, This may not be any help but I'll share it anyway. My bus started acasionally flashing the 'engine trouble' warning light and sounding the buzzer. It was very intermittant and every time it would happen I'd check the oil & coolant levels & find them normal. After this started happening I noticed an oil film on the coolant. This turned out to be due to a bad oil cooler. I replaced the oil cooler and flushed the hell out of the cooling system with dishwasher soap then water followed by 5 or 6 fills of the cooling system with plain water before replacing the normal coolant mix. Since replacing the leaking oil cooler the problem hasn't occured so I suspect that the oil was interfering with the coolant level sensor's function. The moral of the story is check for oil in your coolant. Regards Jerry 4107 1120 | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 134 Registered: 3-2006 Posted From: 209.50.74.6 Rating: N/A |
Ace Usually the low coolant is set to warn and not shut down. It would make sence to set it to warn and if you leave the overheat and low oil to shut down you are well protected. Have you replaced the module that DDEC II uses for the low coolant sensor? Could be intermittent. Bill | ||
| William D. Watkins (Sivrtnge2)
Registered Member Username: Sivrtnge2 Post Number: 175 Registered: 11-2006 Posted From: 70.11.229.202 Rating: N/A |
Hey Ace, I had a ddec 12.7. There is a coolant sensor in the back of the engine head. It will malfunction and cause your exact symptoms. I replaced myself after going into the shop several times with no success. | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 754 Registered: 10-2004 Posted From: 75.201.7.0 Rating: N/A |
Jerry, I had to go and check and there is absolutely no oil in the coolant. Thank god for that huh? Also Bill not sure about your bus but every document I can find on my system (DDEC ll) says that there are 3 things that will shut the bus down. LOW Oil Pressure, LOW coolant, and overheating coolant! There are warnings that will bring up the CEL (check engine light) but still not shut it down! The major ones listed above will shut it down after illuminating the SEL (stop engine light) AFTER the CEL comes on. When that one comes on, you have about 5 seconds to figure out how to get it off the road or you have to use the override switch on the dash! I thought about removing this option from the computer but it's nice to know when there is something quite not right and would really like to keep it if I can! After many minutes thinking over the test we have done and reading the diagnostic book word for word last night, it kept taking me back to an "open 12v switched line"! I have changed all of the sensors and modules and FWIW unhooked and cleaned each and every harness connector I could find or get to and still have this problem but, AHH HAA... the one thing I overlooked and I am seriously thinking this could be my whole problem is on the rear of the bus there is a remote starter push button switch and an ON-OFF-ON toggle switch that allows you or a mechanic to start the motor from the rear engine compartment. These are both housed in a metal box. Both have protective rubber covers on them which tells me they are meant to be kept dry and clean! These happen to be "12v switchs"! DING DING DING! So first thing this morning I go out and remove the box cover. Shezaam the whole inside of the box looked like, well, a rustless mony pit to say the least! I cleaned the rust out of the box and attempted to remove the wire connectors from the switches one by one only to find that they were so far gone, they actually started to break off! Now not claiming to be a whiz kid at wiring, I am thinking this could be my "OPEN" the book is referring to! I have a new box and switch assy. on order and then we'll know for sure when it arrives! All the wires are protected really well thru-out and look to be in pretty good shape! The ends are questionable as this is where most of, if not all the corrosion exist! I will let you know if this is/was/hasbeen the problem from the beginning! Ace | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 853 Registered: 10-2003 Posted From: 71.58.48.5 Rating: N/A |
If the box and switch repair doesn't fix it.... could it be a bad computer with an intermittant? Did you check voltage and resistance readings at the connections AT the computer plug for that particular sensor? | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 755 Registered: 10-2004 Posted From: 216.9.250.63 Rating: N/A |
Yes all voltages were checked out and within proper specs. Only voltage that was low was when I checked the low coolant module voltage after jumping signal wire to ground. It measured 4.9 volts. Then the book says if it's under 10 volts there's an open 12v switched line, Ace | ||
| Jack Campbell (Blue_goose)
Registered Member Username: Blue_goose Post Number: 57 Registered: 5-2007 Posted From: 71.101.164.147 Rating: N/A |
Ace You can change the coolant low to yellow light with your prolink. Low coolant shouldn't put you off the road. Hot that is a different thing Jack | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 756 Registered: 10-2004 Posted From: 75.201.7.0 Rating: N/A |
Yea Jack I know but it doesn't take long after CEL comes on that the SEL is on and then nuttin'! I am going to change the rusted out switches on the remote start box and go from there! Thanks Ace | ||
| Dallas (Dal300)
Registered Member Username: Dal300 Post Number: 180 Registered: 3-2006 Posted From: 209.183.34.45 Rating: N/A |
Ace, I can fix it if ya want. It's gonna cost you though! Dallas | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 757 Registered: 10-2004 Posted From: 75.201.7.0 Rating: N/A |
Looking for warmer weather huh?  Ace | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 724 Registered: 12-2000 Posted From: 98.133.182.133 Rating: N/A |
Did I mention I was to pick the band up for a trip to Yee-Haw Junction for a bluegrass festival? Guess what? They went without me! Ace, Clint barely made it through the show with his sore throat. They did a 1 hour set, which did not help his throat. Jack | ||
| larry currier (Larryc)
Registered Member Username: Larryc Post Number: 161 Registered: 2-2007 Posted From: 207.200.116.13 Rating: N/A |
Ace, if you disable the auto shut down on DDEC 2 that is all that you have disabled. So instead of shut down it goes to half power, so you can get off the road. Not alot of difference but enough to get me to rethink keeping the DDEC. Actually disabeling that feature also stopped all my glitch problems. I did the disable after going thru the same things you are. Levels all checked out etc. I finally discovered that it was shutting off only when I was going uphill and thought about the oil level sensor. I poured in a gallon of oil, and it has never happened again because the next day I disabeled the auto shut down. I guess on auto, any small varience in the wiring can set a soft code and cause a shut down. With the auto turned off, it needs a continuous hard code to shut down. I will shoot my bus before I will ever hook up the auto shut down again! | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 582 Registered: 11-2005 Posted From: 208.54.200.212 Rating: N/A |
Larry, You probably did a wise thing. The problem with a lot of electronics is that most of them operate on very low voltages and the slightest corrosion or other resistance really messes them up. Needless to say corrosion is a major problem on older buses. |