Problem with L400 tempereature gauge

[luckydad]

On the way back from Ocean Shores, Wa. in early July, while towing my trailer, I noticed that the temperature gauge was sitting at about one third from the bottom. We drove home to Vancouver that night thinking nothing of it. The next morning as I fired up the Blue Traveller, the position of the needle on the temperature gauge has not moved. Removing the two wires that attaches to it would put the gauge back to zero and putting back the wires first thing in the morning before the engine has been started brings the needle back to the same one third position.

I have replaced the temperature sensor two times once from Rising Sun with a Hyundai part and the second one a week later from Amazing Auto with an OEM Mitsubishi part. No change. I am thinking (or guessing) that the gauge itself is dead, shot, kaput. Anybody else has had this problem? I would appreciate any solutions you can offer.

Incidentally, I took a gamble and took the Blue Traveller towing my trailer (about 2600 lbs) to Westbank in the Okanagan for a previously planned camping and cherry picking trip with the family this past long weekend through the Coquihalla. 3 adults, 2 kids, bikes and a van full of camping gear. With no pyro and a dead temp gauge, I was doing mostly 60 and 80 kph with RPMs of no lower than 2000 and no more than 2900 rpm on all the uphills. OD off of course. It was slow both ways. Patience was a virtue. During the entire trip, I passed only three bikers on the highway and was being passed by semi's like I was stopped. This was my first trip ever going thru the Coq and had no idea what to expect. Made it back to Vancouver with no overheating, no cracked head but with the same temp gauge problem.


Again, any help would be appreciated.

[almac]

on the l300 there are 2 different sensors.
I replaced one with no change. the other one fixed the problem.
is it the same on the l400?

[davidwwc]

Hi Luckydad,

I think I met you at the rest area on Coquihla and pass you on the way back to Van. Its nce to see you made it back w/o any issue.


DC

[Big-Bird]

According to the engine electrical manual below

http://www.delica.ca/manuals/L-400%20Ma ... TRICAL.pdf

The L400 temp sensor feeds into the glow control relay. Sounds like you have some wire tracing or gauge replacement on the horizon. I do know that the temp gauge can provide false readings if it was jarred or failed internally.

Pages 22-24 of the pdf link below have the test procedure for the L400 temp gauge. Fun!!!!!

http://www.delica.ca/manuals/L-400%20Ma ... TRICAL.pdf

[macro]

I have the same problem, I was just about to post about it!! Changing the sensor with the 'T' shaped connectors did me no good. Unless it's an easy fix wiring issue, it looks like I'm going to have to go to an engine watch dog and an EGT gauge.

Keep us updated on any progress!

[macro]

According to the engine electrical manual below

http://www.delica.ca/manuals/L-400%20Ma ... TRICAL.pdf

The L400 temp sensor feeds into the glow control relay. Sounds like you have some wire tracing or gauge replacement on the horizon. I do know that the temp gauge can provide false readings if it was jarred or failed internally.

Pages 22-24 of the pdf link below have the test procedure for the L400 temp gauge. Fun!!!!!

http://www.delica.ca/manuals/L-400%20Ma ... TRICAL.pdf

I wonder if when the shop installed my manual glow plug switch they disconnected something....

[luckydad]

Al,
I have heard of a second sensor on the l400. I think I had replaced the correct sensor 2x because the temp gauge falls back to zero when I remove the wires. I will however look for the second sensor as a back-up solution. Thanks.

Big-Bird,
Thanks for the links to the manuals. I am mechanically/electrically challenged but will buy an ohm meter to try this out. Looks simple enough. Have to find a weekend to do this. Or get someone to do it for me.

David,
Yes that was me slowly making my way back to Vancouver. Did you also pass that nice and shiny gold Series 2 towing a small boat? I waved at him twice but he just looked at me like I was weird.

[Big-Bird]

According to the wiring schematic there is only one temp-sensor for the 4M40 diesel engine that is connected to the temp sensor.
I checked mine over and have only 1 for coolant. If there is a second one then the schematic needs updating.

I had some discussions in 2012 with Butch at CVI when I thought my glow control unit(GCU) was misbehaving. Turned out to be NFG glow plugs which were new. Headscratcher....must-a-been dropped somewhere during shipping.

The temp sensor is wired back into the GCU to provide an electrical signal so it knows if the engine is cold or not. Its not very likely that your GCU is bad because you said nothing about having trouble starting your Deli. Granted its not that cold right now either.

Test the temp gauge per the procedure (see earlier link) and you might find that there is a bad circuit in there somewhere. Maybe just a loose screw on the back of the instrument cluster. Bad grounds do funny things.