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Topic: Wait to start light not coming on-2004 ISL (Read 773 times) previous topic - next topic

Wait to start light not coming on-2004 ISL

Wait to start light is not coming on at all.  Never happened before.

Is there a relay or other user fixable part?  Only info I find on the schematics says the light is directly connected to the engine interface.
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: Wait to start light not coming on-2004 ISL

Reply #1 –
Could be the bulb.  Does it start ok if you wait?
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Wait to start light not coming on-2004 ISL

Reply #2 –
Can't help with the no light as we don't have the ISL. But as ISL's don't have a glow plug system no engine damage would result in 'not' waiting for the light to go out and would simply be harder starting in cold conditions if the air preheat is not working.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Wait to start light not coming on-2004 ISL

Reply #3 –
Quote from: bigdog –
Can't help with the no light as we don't have the ISL. But as ISL's don't have a glow plug system no engine damage would result in 'not' waiting for the light to go out and would simply be harder starting in cold conditions if the air preheat is not working.

The ISL uses an INTAKE MANIFOLD HEATER-- that is what the "wait light" is about.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Wait to start light not coming on-2004 ISL

Reply #4 –
Quote from: wolfe10 –
The ISL uses an INTAKE MANIFOLD HEATER-- that is what the "wait light" is about.
Yes of course. That won't damage the engine if you crank while it is heating or not heating as the fuel is injected down stream of the manifold heater.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Wait to start light not coming on-2004 ISL

Reply #5 –
Thanks all. 

After cleaning and verifying that the preheat system relays (2 heaters each with its own relay) are OK, no longer have check engine light but still do not have wait to start light.  It has always gone on at start up but it hasn't gone on since the check engine light went on.  So I did something right but not enough.

Coach starts fine. 

There is no 12v out of plug that drives wait to start light so its not a light bulb problem.

As part of checking the relays, I energized them with a separate 12v source and got voltage at the heater posts, about 10.3v.  This must be caused by the load of the heaters since the no load supply is 12.6v.

The relays are Foretravel sourced but are energized from wires from the engine control.   
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: Wait to start light not coming on-2004 ISL

Reply #6 –
The wait to start light circuit has a bulb which I think is used as a timer.  Just saw it is missing from its socket.  This would definite prevent the wait to start light from coming on.  It must of fallen out and I can't find it in the maze of wires behind the dash.  Anyone now the specs so I can get a new one?


Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: Wait to start light not coming on-2004 ISL

Reply #7 –
Found the bulb but no help.  The schematic lists the bulb as "73" which is actually the trade number.  Got one and installed it.  No changes.  Still no wait to start light nor the check engine and engine maint which normally come on when starting and then go out.
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: Wait to start light not coming on-2004 ISL

Reply #8 –
Larry, if you bought an led light-bulb to replace the old one and it is a plug in bulb you might try turn it 180 degrees as the diodes in LED need to be correctly orientated or they won't work.
2002 36' U270 Foretravel
 

FIXED. Re: Wait to start light not coming on-2004 ISL

Reply #9 –
The problems were caused by a partially separated harness connection that ties the Foretravel half if the engine warning info to the Cummins half.  I started to suspect something like that as the only thing common to all the symptoms. 
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee