2005 Dodge Ram 1500 - occasionaly won't start. Starter solenoid has a short initial click. Always fails when attempting to restart witin 0-15 minutes of turning off. Starter & battery replaced. Fails with both keys. No engine codes. No unusual dash lights. Always restarts successfully after waiting 3-5 minutes. Any suggestions?

 

Welcome to DF! I will move this to the appropriate Ram section.

 

Sounds like the ground coming off of the starter is bad.

Follow the black wire from the starter to the chassis take off the bolt clean the area and the connector and remount.

That is the most common cause of that problem.

Or you may have a bad starter relay that is sticking open, simply replace that relay.

If none of that works then you may have to dig into the wiring with a multimeter and measure currents and voltages and seeing what is actually going on.

 

Already swapped out the starter relay & checked the starter ground. Any way to determine if it is part of the truck's immobilizer feature? It seems that from a pure mechanical sense that the starter components & electrical delivery to the starter is fine. What else could prevent startup from a PCM perspective other than immobilizer or maybe a sensor that triggers prevention for safety reasons? I gues if it was a sensor that is preventing startup a code should be generated.

 

Well there are a few things that can prevent start-up:

1) Insufficient Fuel - Most common is fuel pump is starting to fail and is not priming fast enough.

2) Timing is off - Most common cause is a bad crankshaft sensor

3) Insufficient power to PCM - Most common causes are a bad ground at the PCM or a corrupt program, and/or a bad battery cell causing current drop during starting.
Current is just like water, it takes the path of least resistance (where it can flow most freely) so if there is a bad cell the remaining cells will try to flow through the larger gauge wires rather than the smaller, so the PCM gets shafted.

Those are the most common issues with failing to start, you can basically break them down into:

1) Fuel Problem

2) Mechanical Problem

3 & 4) Electrical Problem

If you were having a problem with the ignition immobilizer you would see additional lights lighting up when you are trying to start that would indicate that the anti-theft system is being triggered.

I'm not saying it's not possible that the immobilizer is the problem, but it's not very common. To check this you would need a DRB-III (or StarScan) diagnostic tool in order to monitor the output of all of those systems, so it's a job for the dealer to complete.

I've seen a problem with immobilizers on VW's and Audi's and most of the time it's a little bit cheaper to replace the immobilizer than it is to have the dealer troubleshoot it, b/c half the time they don't know what they are looking for. In all honesty I am not sure how hard it is or how many parts will be needed, but most of the time the immobilizer is integrated into the "brains" of the anti-theft box that also controls all of the door sensors, stereo deck, and a bunch of other systems.

What might also be happening is the sensor that picks up the key fob might not be working properly, and on most cars they are integrated into the keylock cylinder, which forces you to go to the dealer for the parts, b/c it has to be matched to your key.

I also forgot to ask you, do you have any modifications done to your truck?
(things like a power chip/programmer can cause issues like this too)

 

It could be the solenoid itself sticking, but more than likely you are having a ground issue. If your have someone try to start it when it is clicking like that and you watch under the hood I can almost guarantee you will see arcing. What happens a lot is the ground from the block to the frame corrodes (back of the block near the passenger side, back of the head). The best solution i've found is to add a ground wire from the block (I think there are a few options near the a/c compressor), and run it to the frame ground near the front of the driver side wheel well (double up the ground here). this gives you a full circuit preventing the arcing. If it's not the starter, this is your issue, trust me. A good check is to get an advance auto battery test (hopefully when the condition is happening), or if you have your own tester, and the battery voltage should check out ok, but you will get a low voltage going to the starter.

 

If it does arc it's much easier to see at night... in the daytime you will almost never see it.

 

Some good suggestions to try. The frequency of this trouble is only about once or twice a month and lasts less than 5 minutes and invariably happens where any troubleshooting and analysis is really difficult. I will recheck the ground connections as a first step and keep my fingers crossed.

One curious observation...I bought the truck in 2012 (2005 RAM 1500 with only 25000 miles) but noticed wax markings on *******ly every engine component. It was sugested that these markings were typical mechanic marks used to assist troubleshooting which leaves me beleiving that this problem has been around for a while....maybe even since new.

 

oops. ********ly should read "*******ly"

 

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