what tests can i do, as the abs light has come on, radio doesn't work and the overdrive light is flashing on the automatic shifter. i ohmed out the rear diff sensor it shows normally close at about an ohm-1.5 checked pigtail it's open circuit, note these tests were done with engine off
I mentioned above in the question area
Hi, I’m Chris. Welcome and thanks for asking your question!
Does the speedometer work when driven?
Does the radio do nothing at all?
radio does nothing, fuse 17 blown, says it's the rabs/psom fuse. if i replace it with a 50 instead of a 20a it will turn the abs light off all normal radio comes on/clock, but the it will start to smoke and melt the plastic on the 50a fuse as well. has all new glow plugs, wiring harnesses, idm110 etc. speedometer does not work.
Thanks for the info.
You need to unplug the ABS under the hood and the PSOM at the back of the instrument cluster. Then Ohm test the fuse holder to ground to see if the circuit is still grounded. If it is then you have a bare wire from the fuse panel to both of these components chaffed and touching ground. If you show an open circuit then test each component to see if this circuit is grounded which will indicate a new part is needed. See the diagram below for the wire color and connector pin numbers.
On the radio, you need to remove it from the dash, use these directions. http://wikisend.com/download/406134/1121.pdf Then you need to check each power and ground. If there all good then the radio is faulty.
16 years experience with Ford.
I haven't had an opportunity to put your options into effect and try yet, however I do have a PhD in Electronic Engineering so just from what you said I have no doubt I'll be able to find the problem. Just needed a shove in the right, the dang mechanics around here have, for the work I mentioned that has already been done gotten me for about $9K. Getting a little ridiculous I thought. Thanks again Sir. Awesome answer, diagram and instruction on what goes where and why. Appreciate it greatly
Glad I could help, just let me know if you need anything else.
Okay, I had a chance to do the checks you've specified and this will seem odd maybe not to you. If I disconnect, even cut the two wires going to the psom and abs module behind the speedometer and put a fuse back in and turn the key to the on position, not starting the van, fuse still blows. if i check the wires i cut it shows NO short. in the fuse holder i do get from each side of the fuse holder to ground as "okay" per your response. Which I think you'd said would indicate a bad component but wtf, which one now?? I had all disconnected, the radio by the way they had tied to the same two wires is why it was out as well. Now get this, if I put say a 50a fuse in the holder, everything will come on and work fine for a few minutes and then it will start to smoke. Appears the smallest of shorts in the circuit, but I disconnect all the /psom/abs module/under the hood and the "single module behind the passenger dash". still get blown fuse. what on earth am i looking for now? any other components that those two wires go to ie transmission etc. I did have a new jasper/reman put in about 2 years ago and has a three year warranty. Just let me know. Still giving you 5 stars, I just can't keep spending thousands of dollars on this old van but it's all I have for a full service van for an Alarm Systems company I own here in Elizabethtown Ky and have since 2005. Let me know man. Appreciate all the help.
Thanks for the great update.
The fuse only powers the things mentioned 2 or 4 wheel ABS and the PSOM. This indicates you have a short i n the wire harness where as this wire is chaffed and touching ground.
Just before having read your info I got it. If I remove the radio fuse all is well. Either radio is finally going under or wire's chaffed somewhere on it's line I reckon. Who cares.?? LOL It's a 7.3L Diesel you can't hear the radio anyway ha. Thanks for all your help. Issue resolved- Terrance
110% excellent sir. Thank you again
Glad I could help