Re: Turn Ignition Key To Start , But Starter Won't Engage

[jeffecito]

'I'm not getting 12VDC from the ignition switch start position to the Starter Relay small terminals (It cranks when large terminals jumped). This means that I'm probably not getting 12VDC to other components, like the fuel injector pump etc that are necessary to start the engine.

However, the oil pressure light now goes on and the needle indicates 50 psi, and inlet air temperature no longer lights, when turning the ignition key to the on position

I can't find my ignition fuse to check it.  Anyone know where it's hiding?  Or a possible solution to my above situation?

'96 Safari Sahara, Magnum Chassis, PA 1056, MfD ID 99-2154, 3126 Cat 300hp, motor s/n IWMO1477, Mod# PA-8732-02, OEM # 008-20009, FLS-16

'

[7646ptrtcwo6o3ywrf6o4hn4hwtaar23ciq45kjz]

'Jefficto, I don't know about jumping anything, but I did have problems starting and was suggested to me it was either ignition or ignition selenoid. I changed out the selenoid from NAPA for $54 and walla, that was my exact problem. 12v 85 amps continuous is the selenoid description. Good luck

PJ
1999 Serengeti
330 Cat'

[jeffecito]

'Thanks PJ, I'll take a closer look at the relay.  I hope that's it.

Jeffecito'

[robert.lewis.tl@gmail.com]

'Hi
I just went through two weeks of troubleshooting and repairing a short on my dash (just bought the coach in that state). Here are a few tips that might help you.
What you should start with is check the bus bar in the main relay panel if you think you are loosing 12v. On my 2000 Continental it is the small bay directly under the drivers seat. That is where the reset fuses are. They are not like a normal car, they will trip and reset once the problem is removed. I found someone had put a 15a fuse where there should have been a 20a fuse. The voltage was there but if a load was applied it went away because the relay tripped. One of many such issues. This is probably not your issue, but there should be a fuse diagram with values on the bay wall.
In my unit all the dash components are fed from that panel. If you have 12v coming in to the bay and going out then the problem may be somewhere in the dash. But check the voltage level with a multi-meter. If there is a short you will see a significant drop from 12v, Normal voltage should be around 12.4 - 13v no load. On my unit some RV shop had added lines to my harness under the dash and shorted out the tail lights. Because these coaches have each signal having a separate grounds and heavy wire, the short can melt a wire a long distance from the short ie the weakest link/wire. In my case the tail light bulb melted the lens but the short was under the dash. I had to remove a lot of add-on wiring to narrow it down and cut the harness in about 50 places. As a side note if you need to repair the harness, don't use crimp connectors. You can get something called Sopoby Solder connectors that uses an inexpensive heat gun to melt the low melting point solder. The connectors are heatshrink, solder and waterproof. You can get them on ebay. 
But if there is no 12v power then there may be a relay in the engine compartment. Mine had a disconnect relay to the ignition switch in the battery compartment tied to an elaborate security system. A clamp on current meter helps to see what current is being drawn when everything is off including the invertor. Also if you have a cable piercing probe that is a big help. It has a very small pin that punctures the wire shield without damaging it.
Look carefully at the wires, they all have names on the shield every 6" or so. 
Robert'

[robert.lewis.tl@gmail.com]

'I overlooked the obvious because of my own experiences and because you said you didn't have lights etc working. I could just be a bad ignition switch. Use a meter to check that 12 v is going into the switch and then going out when in the on position. If you do not have working lights unrelated to the ignition position, such as park lights when the dash light is pulled on, and dash lights, speedometer etc, then the ignition switch is not the problem. These lights are on different circuits.
Robert'

[jeffecito]

'Thanks Robert for your input.  I now have new places to look for the problem.
The connectors are new to me.  I'll be getting some.'

[jeffecito]

'I've only found the inlet air temp light that no longer goes on, but I'll now check for any others that I may have missed. 
Thanks,
JH'

[QuantumRift]

'JH:
Back in March/April I had the same issue, unfortunately it died when the coach was at the RV dealer and we had it towed to a Freightliner shop in Zanesville where I had no access to it.
Having said that, and after it was all said and done, and after I'd gotten ahold of decent schematics, the problem was with the wiring in the back of the chassis, behind the maintenance panel and battery compartment. Now the tech at the shop, didn't have good schems to work with and eventually ran another wire to the ignition switch. However, after getting the coach back and examining things, there were broken and corroded wires off the Start and Stop switches on that panel, and I found three uncovered fuses dangling behind the batter tray. One was  30 amp fuse that when disturbed (by shoving in the battery tray, while engine was running) killed the engine. 
The other wiring issue seemed to center around the 'mystery relay' that we discussed on my thread at length. You can read thru that thread as well.  The wires coming off the start and stop switches are all tied into that as well, and as it sits, I chose not to investigate any further as to the possible issues for fear of inducing more problems - it's working and I don't use the rear panel start/stop switches.
I also found suitable covers for those three hanging fuses behind the battery tray as well. 
Doug96 Serengeti 38'Cat 3126



---In Safarifriends@yahoogroups.com, wrote :

I've only found the inlet air temp light that no longer goes on, but I'll now check for any others that I may have missed. 
Thanks,
JH'

[jeffecito]

'Thanks Doug,

I'll look up your prior thread for more details.  Now I just need to find time to tear into it.

JH'