QuestionQUESTION: Hello,
I have a 2001 Chrysler Intrepid 2.7L that is having a starting issue. I turned the key and nothing happened and no dash lights came on. I changed the battery, battery cables, ignition switch, and all relays and fuses on the PDC. I turned the key and did get my dash lights and radio that I wasn't getting earlier but when I tried to start the car the ING START/RUN fuse popped. I replaced the fuse 4 more times and got the same result. What could be causing the 40amp fuse to pop? I also checked the battery wire that runs to the PDC for any breaks and retaped it just to be sure.
Thanks.
ANSWER: Hi Michelle,
Thanks for the clear accounting of the problem. The only fuse that is not called into play until you move the key to the 'start' position is fuse G which is the outboard-most fuse in the back row of the double row of 7 fuses (the manual doesn't tell me which fuse is labelled IGN START/RUN). Let me know if that is not the fuse you are describing.
That fuse also powers many other circuits in the 'run' position of the switch, but evidentally those circuits don't overdraw the fuse and blow it. It is only when you add the draw of the starter motor relay (and transmission computer which shouldn't draw much current) that the fuse blows, which leads me to suspect that the relay or its circuit are drawing too much current in addition to those other circuits and thus causing the fuse to blow. I would believe that if you remove the starter motor relay that then when you again try to start it that the fuse G will not blow. So check that hypothesis out.
If it doesn't blow then that would suggest that the relay is bad (shorting its current supply from the fuse to operate the actuation coil directly to ground). You could verify that the a/c compressor clutch relay nearby has the same part number as the starter motor relay, and if it does, try removing the starter relay and substitute the a/c relay in its place. That may resolve the problem and you would then get a replacement relay for the a/c relay you 'borrowed' to do the test. I believe the relay purposes are shown on the box lid, but if not, the starter relay is the 4th position from the in-board end of the box, and the a/c relay is the sixth position from that same end.
If it blows then that would suggest that the wire from the fuse to the relay is shorted OR that the wire from the fuse to the transmission computer pin 8 is shorted to ground. I can describe how to check that out if necessary. It would be helpful to have a volt-ohm meter for that purpose if necessary.
It is possible that there is something drawing too much on the fuse when it is in the run position but not enough to blow the fuse until you add in the starter relay. That we will need to use the meter to analyze as well.
So give that a try and let me know what you find. If that doesn't resolve the problem tell me whether or not you have access to a volt-ohm meter. It is expensive to troubleshoot by repetitively blowing fuses!
Roland
PS Please 'rate' my answer and where you see the question about 'volunteer of the month' please consider a 'yes' answer if this response proves helpful. Thanks
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QUESTION: sorry, I forgot to mention that the fuse that keeps popping is on the PDC.
could the alternator wire cause this issue? I just noticed that it may have come loose from the bracket and hit the radiator fan causing some of the insulation of the wire to be chewed up. maybe a grounding issue?
ANSWER: Hi Michelle,
You didn't say which wire (orange/dark green or dark green) at the alternator came loose but neither of those wires is powered by the fuse G which I believe is the one that is blowing.
Roland
PS: I just noticed another 'draw' in fuse G: the starter motor solenoid switch is activated by current also coming from that fuse when the starter relay is activated. So in addition to the relay actuation coil we the possibility that the starter solenoid switch is at fault. I suspsect in fact that the starter solenoid switch is more likely the probem than the starter motor relay, and for that reason I would try the following before doing the relay substitution that I first suggested:
The only way to test that solenoid switch faulty possibility would be to try a jump with a thick wire from the battery + post (or the battery wire you identified as coming into the PDC would also do) directly to pin D of the starter motor relay socket (after removing the relay). Pin D is the middle pin of the socket (larger in size) and I would simply touch the jumper wire quickly to that pin socket because if the solenoid is shorted the wire is going to carry a lot of current and get hot fast because it will not be fused. Either the starter motor will respond or the wire will get hot. If the former then the solenoid is not the problem. If it doesn't respond and instead the wire heats quickly then I believe you need to remove the starter motor and have it rebuilt which will include replacing the solenoid switch. Generally the solenoid switch is not easily replaced without taking the motor partially apart so the rebuild is the usual procedure.
Of course there is always the possibility that one of the wires involved in these circuits on fuse G has frayed insultaion (like you hypothesis about the alternator wire) and is grounding and thus blowing the fuse. That is something that we would only get into if we are unsuccessful in focusing on the relay and the solenoid switch.
Sorry I didn't include this possibility in the first answer.
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QUESTION: Thank you for ideas to try. I will try the suggestions above and let you know how it goes.
AnswerHi Michelle,
I will await the results. Be careful when you are dealing with a jumper that is connected to the battery wire or battery + post) without there being a fuse in the wire because if you have one end of a wire connected to the battery and you touch the other end to something that is grounded (meaning essentially that is connected to the other - post of the battery) it can carry a huge current and get red hot almost instantly. So you want to just touch it to the suspected faulty point to test for a response, while having some thermal insulation on you hand so you don't get burned. If you had a volt-ohm meter you wouldn't have to troubleshoot it this way, rather just measure whether the resistance between the suspected point were 0 ohms (a dead short), or something a little bigger than 0 ohms (which would be like solenoid switch coil or relay switch coil which is OK).
Roland
