1998 Patriot dash gauges dead

[Dennis Clevenger]

Yesterday about 50 miles from our destination I saw that the voltage gauge was at zero.  I immediately freaked and shut off the lights and fans, thinking the alternator may have taken a dump.  Then it came back up to 12v and shortly after went back down.  A little bit after that I noticed the engine and trans coolant levels appeared lower than usual.  Well, they were static, not moving, as I normally watch the coolant temp closely.  So a few miles down the road I’m watching the Magnum ID.  It showed voltage at 13 volts, engine at 187 degrees and trans around 220.  Cool, so I can relax, it’s just the analog gauges are hinky.  Today checked breaker for instruments in elect. bay.  Checked ground continuity from all gauges to the ground bar under the dash.  RVDiagnostics guy guided me through measuring ohms from signal wire (each gauge) to ground.  All checked out.  Disconnected 3 big black bundle connectors in elect bay and reconnected, no change.  Also found a large grey round connector under front left fender, opened and closed that, no change.  Looked under bed to inspect any bundled connectors.  Nothing but bundle of wires leading forward.  Looked under engine on passenger side, saw no connectors from there.  Sooooo…, anyone have any ideas of where/what to look for?  Thanks in advance!

[Eric Maclean]

Dennis
Each of the gauges in the dash are feed 12+volts to the I terminal on each gauge this power is daisy chain from one gauge to the next.
Each gauge also has a ground connection on the G terminal on each gauge daisy chained from one to the next.

With the dash out check between the I terminal and the g terminal with a volt meter and the ignition turned on it should read battery voltage if you have a 12 volt reading the voltmeter should read 12 volts
First using a volt meter to read the voltage between the ground buss bar and the ignition solenoid with the ignition turned on check the voltage on both sides of the solenoid ( large studs) your are looking for a volt drop across the solenoid if there is more than a volt difference from one side to the other the solenoid is bad .next take a volt reading at both sides of the circuit breaker for the gauges if they aren't the same as at the solenoid the breaker is bad.
If the breaker is cycling on and off you may have a short circuit in the gauge feed circuit causing the breaker to cycle ( shorted wire or gauge)
If no 12 volt reading between  the I and g terminal on the gauges start by running a jumper with directly from the ground buss bar in the electrical bay to the G terminal and do your test again.to verify weather it's a ground problem or supply problem if you still have no 12 volt reading move your jumper wire to the I terminal and connect the other end to the ignition side of the ignition solenoid in the electrical bay.to verify the gauges read correctly


Sorry for the long winded instruction I hope it helps you determine where to look for your fault
Eric

[Steve Huber Co-Admin]

Dennis,
In addition to Eric's advice, (assuming the dash meter connections are held in place with threaded nuts) be sure to check the tightness of each nut. I had a similar problem on my 01 and found most of the nuts were not tight, causing intermittent connections.
Steve

[Dennis Clevenger]

Thanks Eric, we’re traveling tomorrow, so I’ll test your suggestion in a day or so.  Will let you know results.

Thanks!

Dennis

[Dennis Clevenger]

Thanks Steve, I did check tightness of all S, I and Grd nuts but am now thinking of loosening, move the ring connection a bit and re-tighten.

Dennis

Dennis,
In addition to Eric's advice, (assuming the dash meter connections are held in place with threaded nuts) be sure to check the tightness of each nut. I had a similar problem on my 01 and found most of the nuts were not tight, causing intermittent connections.
Steve

[Brian Furlotte]

Last summer I had issues while driving down the road some or all of my gauges would falter on and off.  It started with just a couple, then more.  Would last a few seconds, then come back on.  Started getting more and more common but the motor never hiccupped. 

Then one morning getting ready to leave a campground, the coach was idling as we were getting ready to pull out of site and it just died.  Odd.  Started it back up and everything was fine.  Then the gauges went dead and several seconds later the engine died again.  Searched on here and the 12v ignition solenoid in the electrical bay was suspect.  (Eric mentions this above)  So I got the meter out, checked voltage and had wife start coach.  Sure enough, strong voltage coming in, marginal coming out and then it dropped lower until motor stopped.  Replaced that relay and problem went away.  Two screws to mount solenoid and a couple of nuts to hold ignition wires.  I now carry a spare.

Might be it, unless I really missed reading your description, which is always possible!  Good luck