Thursday, June 12, 2014

Making the Best of the Unexpected

A rotten tooth, severe t-storms, tornado warnings, high winds, and now the RV’s check engine light keeps coming on.  I’m beginning to think this trip might be cursed.   So far, we’ve had to delay the trip and change our route to dodge storms.  Now the RV is acting up.  

My rig is a brand new 2014 Winnebago built on the Mercedes Benz chassis.  It’s got 11,000 incident free miles, up until Friday when the Check Engine Light (CEL) came on.  I’ve worked on gas cars and trucks most of my life but this diesel is new to me.  I’m 2,000 miles from home, so this light puts a knot in my stomach.   The manual says it could be something with the emission system malfunctioning and that I’ve got 500 miles before the vehicle may start to shut things down.  Great. I’m in the middle of “nowhere” Kansas, 200-300 miles to the nearest dealer.  That’s the thing about a Benz, it’s got a unique diagnostic system and codes that can only be worked on by a service dealer with the proper computer system.  Local repair shops can’t work on it.
When it first happened, I called my roadside assistance that I signed up for when I bought the rig. I talked with a Sprinter tech who said it may be a loose fuel cap giving a weak fuel pressure reading.  She said that the Sprinter has known issue with the CEL if you don’t fully tighten the fuel cap the CEL will come on.  She suggests I reset the cap and drive a few miles.  She says that if it was the cap, then the CEL will go out after 2-3 restarts.  Well, low and behold, 40 miles down the road and 3 restarts later, the CEL is out.  Hallelujah!

But, a day later it happens again while we’re in Dodge City, KS.  But, then it goes out again.  I figure this is something I should have checked out before I go to the Navajo reservation in northern AZ where I know there will be no Benz dealers for 500 miles.  It could be a voltage problem or faulty sensor.  So, its 180 miles back east to Wichita where the nearest dealer is located.  We spend the night in Wichita and get to the dealership on Monday am and they take me right in.  MB dealerships are great. They must figure if you can afford a Benz then you deserve lavish treatment.  The waiting area has free food and drinks, a fireplace, free wifi, and a large flat panel TV.  The bathroom has neatly rolled up face towels to wipe your hands on just like a fancy resort hotel.

The tech plugs his monitor into my rig and finds no problem.  Great.  A 360 mile round trip to find out I have no problem.  But, it gives me somewhat of a piece of mind that I had it checked out.  So, its back to heading west towards the Rockies.   

South eastern Colorado is sparse and beautiful for its vast 20 mile views and emptiness.  It’s cattle country with short grass giving way to rocky scrub land.  As we drive west on Rt 50 and then Rt 160, the Rockies appear as small dark blue/purple jagged silhouettes on the horizon of the plains.  They grow to towering snow capped monoliths as we keep moving west.  We pass thru several small western towns that seem to have had time stand still since the 1950s’ with their old brick buildings, ancient filling stations, and stores lining a Main Street (e.g Rexhall Drug Stores).

The Rockies in Southeast Colorado

On Rt 160, past Walsenburg, we climb up 9,400 ft to La Veta Pass.  This is just a foot hill to what will come.  Then it’s down to a vast high plain 60 miles to Alamos and to the foot hills of the San Juan Mountains.  At South Fork, we start a major climb several miles up to Wolf Creek Pass at 10,200 ft and cross the Continental Divide.  It’s a dramatic road, complete with tunnels and jaw dropping scenery.  It also has some fairly steep long downgrades requiring slow going in a low gear.   
Descending Wolf Creek Pass

Cav at the base of Wolf Creek Pass

At the base of Wolf Creek Pass, the CEL comes back on.  Bugger!!  I was so hoping after 500+ incident free miles that this problem was behind us.  Then my DEF alarm comes on.  I had just refilled it so something is definitely wrong.  We make it all the way to Durango (100 miles) with two alarms on, but then the vehicle tells me I have 10 restarts left before it will stop starting.  Great.  The nearest MB dealer is in Albuquerque (210 miles away) so I make an appointment for the next day to get this checked.  Another setback, but what can you do – it’s got to be looked at.

So, it’s a “short” 210 miles southwest along Rt 550 to Albuquerque.  We get there at 1pm and the service manager takes us right in to get it looked at.  So far, my impression of MB dealerships is very very positive.   They have been very responsive and helpful and get us right in to be serviced without an appointment.  I even get to go in the garage and chat with the tech as he diagnoses what’s wrong. 

The fault codes say my DEF exceeded its low point and that is what put the alarms on.  All the sensors check out and give off no error codes.  The tech theorizes that the DEF tank sensor needed to be re-calibrated with the on board computer based on how I was filling the tank.  I’m amazed.  My Benz has 36 sensors and he checks everything out on a laptop never picking up a wrench, tool, or a rag to wipe his hands.  He can see all the temps, particle counts, engine performance, and voltages from his computer.

We top off the DEF again and he calibrates the tank sensor with the computer.   I learn that I should top off the DEF every 500 miles and not to let the alarm go off.  If the tank consistently gets too low, the sensor can get out of calibration and cause the problem I had.

So, we’re off again, back to Durango.  I had to cancel a couple of reservations but we’ll see what we can do to pick them up on a new schedule.  New Mexico was an unexpected stop but it was a technical learning experience for me and a new visual experience for Cav – The Land of Enchantment.  We got to experience Rt 550 down to Albuquerque.  A pretty road but very desolate.  It was super hot and dry in Albuquerque.  Temps in the mid 90's and humidity down to 7!!!!. We spent the night at Coronado State Historic Park about 10 miles north of town.  A nice park and the price was right at $20 for AC and water, which we needed.

At Coronado State Historic Park in Bernalillo, NM


  1. Good intel on the DEF tank top-off. Thought you could run it to close to empty as long as it didn't completely run out. Thanks!

    1. My View has a 3.2 gal DEF tank. I could go about 3,500 miles before the alarm would go off. With the small tank, when the DEF gets low and starts sloshing around it can throw off the level sensor. I always top off it off around 500 miles.