HELP! Flashing Wait to Start Light

[gipperkid]

So I have had the first major problem with my 02 2500. Got the truck out Saturday afternoon to go to a church dinner. Get ready to leave the dinner and my truck won't start. When I key-on the ignition I don't hear the FASS kick on, then I notice the wait to start is flashing. So obviously I am assuming the worst, a dead ECM. The truck would just crank and crank and crank. Call for tow and of course it will be awhile, so I leave the truck and wait at home.

(A side note, before I left the house that day when I first got in the truck and turned the key on, the FASS was delayed in kicking on. Thought it was weird, so I turned the key off and back on again and everything seemed fine. I figured it was just a fluke.)

2 and 1/2 hours later I get the call from the tow driver. I get there and of course human nature tells to try and start the truck. Turn the key on and the FASS kicks on, and the WTS illuminates with the normal delay since it was cool outside. The truck fires right up. I get out to thank the driver for coming and try to pay him for a dry run, and then the truck dies. WTS flashing and will just crank. So had it towed home.

Sunday morning same thing, key-on, no FASS, and flashing WTS. I decided to clean the battery grounds, they were somewhat corroded. After cleaning the grounds, truck fires up, runs for about 10 seconds and dies. WTS flashing. I then cleaned all the terminals. Now when I key-on, the FASS kicks on for the brief second, the WTS illuminates and stays on indicating for the grid heaters. But by now the batteries are so weak the truck won't turn over. I tried charging and boosting each battery, but it would barley crank. 

 

So can weak or bad batteries cause this issue?

 

Intuition leads me to a bad ECM, but the truck ran a couple times, and the WTS is not delayed. I did the key trick for codes: P PCU - p1693, p1694, P ECU - showed no codes. But I will still put the scanner on it. Does this sound indicative of a bad ECM? I do NOT have a No BUS message either.

Bad IAT sensor?    Bad grid heater relays?    Bad grid heater?    Corroded grounds?

Open to input, suggestions, any help!

 

Edited March 11, 2019 by gipperkid

[JAG1]

I had a bad starter that would almost empty the batteries of everything they had in them. While trying to jump start with another truck, it drained both those batteries in almost an instant. as well, but before you jump to all the expensive possibilities ..........

 

Do you have the fass powered by the batteries  thru a relay? or is it connected to the factory lift pump power connection? In any case, you need to get the lift pump off the factory lift pump connection because when the lift pump goes bad it can burn up the ECM

 

What condition is all the rest of the electrical?

 

I would also disconnect the grid heaters. Could be drawing down already weak batteries from corroded connections and constant under charged batteries. You can plug in the block heater instead about 3 hrs ahead of time to avoid the grids. Unhook the grids at the drivers battery. you'll see two black wires going into one wire with the ring terminal on the end.

 

 

Edited March 11, 2019 by JAG1

[gipperkid]

Just now, JAG1 said:

I had a bad starter that would almost empty the batteries of everything they had in them. While trying to jump start with another truck, it drained both those batteries in almost an instant. as well, but before you jump to all the expensive possibilities ..........

 

Do you have the fass powered by the batteries  thru a relay? or is it connected to the factory lift pump power connection?

 

What condition is all the rest of the electrical?

 

I would also disconnect the grid heaters. Could be drawing down already weak batteries from corroded connections and constant under charged batteries. You can plug in the block heater instead about 3 hrs ahead of time to avoid the grids. Unhook the grids at the drivers battery. you'll see two black wires going into one wire with the ring terminal on the end.

The FASS is connected to the factory LP connection on the engine harness with positive and negative for the relay connected directly to the driver battery.

I am going to throw two hot batteries in it and at least try that first.

Condition of electrical as in corrosion? That is something I am going to do is clean all the terminals and ground points. All the factory grounds and wiring placement is still factory. I thought doing the battery cable upgrade. And I have never seen any issues so I don't think AC noise is an issue. Also thought I about just getting a Nations or Mechman alternator as preventative maintenance.

 

I have boy scouts tonight with my so there might be enough daylight left tonight to mess with it.

[Mopar1973Man]

1 hour ago, gipperkid said:

Bad IAT sensor?

 

The truck will function without an IAT sensor.

 

1 hour ago, gipperkid said:

Bad grid heater relays?

 

1 hour ago, gipperkid said:

Bad grid heater?

 

You can delete the grid heater all together still start and run normally. Common in the south.

 

1 hour ago, gipperkid said:

Corroded grounds?

 

All the important ground are hooked to the passenger side ground terminal. 

 

Flashing WTS light is a bad news deal that points to internal ECM problem. Booting issue or EPROM issues. Mostly caused by excessive AC noise from the alternator. 

 

 

[gipperkid]

Just now, Mopar1973Man said:

All the important ground are hooked to the passenger side ground terminal. 

 

Flashing WTS light is a bad news deal that points to internal ECM problem. Booting issue or EPROM issues. Mostly caused by excessive AC noise from the alternator. 

 

 

Even though the truck started twice, of course it only ran for about 10-15 seconds.

So with the ECM it's like an old windows computer where it freezes on boot or blue screens?

Would I be to swap an ECM from another truck? I have a few ECMs laying around.

• 2001 w/Auto, ID 3946242
• 2001 w/Manual, High Output
• 2000 w/Manual, ID 3946242

[Mopar1973Man]

ECM's are like a PC. It's got a hard drive (EPROM), BIOS that tells the CPU to boot the EPROM. CPU and Memory to run the software. So when there is issues either the WTS light doesn't come on or it flashes to note issues. 

 

I highly suggest you don't swap ECM's there is about 52 version of software per YEAR. I would suggest just having your current ECM repaired and put back into service this way there is less problems with software issues. I've seen issues where a swapped ECM refuses to talk to the PCM because of software differences. I've seen all kinds of weird issues with swapped ECM's.

[gipperkid]

Just now, Mopar1973Man said:

ECM's are like a PC. It's got a hard drive (EPROM), BIOS that tells the CPU to boot the EPROM. CPU and Memory to run the software. So when there is issues either the WTS light doesn't come on or it flashes to note issues. 

 

I highly suggest you don't swap ECM's there is about 52 version of software per YEAR. I would suggest just having your current ECM repaired and put back into service this way there is less problems with software issues. I've seen issues where a swapped ECM refuses to talk to the PCM because of software differences. I've seen all kinds of weird issues with swapped ECM's.

Well I know I need two new batteries. Is it worth my time trying troubleshoot, or should I just pull the ECM and send it to ACS in Florida?

[Hawkez]

I would certainly troubleshoot some more.  If you send your ECM in you'll need to know the codes.  Get a scanner and get the codes.  There are troubleshooting tables on this site that you can run for each code.  I would at least start there.

[Mopar1973Man]

4 minutes ago, gipperkid said:

Well I know I need two new batteries. Is it worth my time trying troubleshoot, or should I just pull the ECM and send it to ACS in Florida?

 

You could but...

 

1 minute ago, Hawkez said:

I would certainly troubleshoot some more.  If you send your ECM in you'll need to know the codes.  Get a scanner and get the codes.  There are troubleshooting tables on this site that you can run for each code.  I would at least start there.

 

He's got a point you need to have some info. ACS will at least bench test it before starting. You can call them and ask about the WTS light issue and dying out. 

[gipperkid]

I'll report back once I get the scanner on the truck. Hopefully will be able to tonight.

48 minutes ago, Hawkez said:

I would certainly troubleshoot some more.  If you send your ECM in you'll need to know the codes.  Get a scanner and get the codes.  There are troubleshooting tables on this site that you can run for each code.  I would at least start there.

Is there something that I possibly missed as far as troubleshooting that you could recommend?

I'm throwing two fresh batteries in, cleaning connections, scanning for additional codes.

[Hawkez]

I would start with the codes that you can pull with a scanner and not just depend on the key trick. 

[Dieselfuture]

You can put the different ECM in for testing purposes but I wouldn't leave it in for too long. You need to figure out what fried your ECM in the first place, seems that most common problems are alternator and ground wires

[Mopar1973Man]

3 minutes ago, Dieselfuture said:

You need to figure out what fried your ECM in the first place, seems that most common problems are alternator and ground wires

 

That's exactly right. Need to figure out what caused the failure. Other than that you'll continue to replace ECM and get frustrated.

[gipperkid]

11 minutes ago, Dieselfuture said:

You can put the different ECM in for testing purposes but I wouldn't leave it in for too long. You need to figure out what fried your ECM in the first place, seems that most common problems are alternator and ground wires

 

 

8 minutes ago, Mopar1973Man said:

 

That's exactly right. Need to figure out what caused the failure. Other than that you'll continue to replace ECM and get frustrated.

 

Will any of the ECMs I listed be fine? It seems that they all share the same ID number regardless of year or trans type.

But yes I am just going to go ahead and get a nations alternator and do the W-T ground mod. 

[Dieselfuture]

I would pick the one closest to your truck, year, tranny, etc

[gipperkid]

1 minute ago, Dieselfuture said:

I would pick the one closest to your truck, year, tranny, etc

I'll try that as a last resort if all other troubleshooting fails.

[gipperkid]

@Mopar1973Man

 

Ok, so I pulled codes with my basic bluepoint scanner. Did this before swapping batteries. Only codes the scanner was able to pull were P0216 and P0230. Also before swapping batteries I could key on and get the brief second of the lift pump and wait to start until the grid heater kicked off.

 

Swapped batteries, cleaned the terminals, and got the terminals reconnected. Turn the key, and get normal operation of the LP and WTS. Truck starts and runs. Let it run for a good 20 minutes. I get the truck in the garage and I notice I have no throttle when I press the pedal. It comes and goes, then the truck starts to lope and then just shuts down. And now the WTS is flashing again.

 

I couldn't pull any DTCs with the scanner, says unable to connect. And with the key trick I get P1693 and P1694. I didn't have the big scanner just a basic one.

 

Where to go from here....?

Edited March 12, 2019 by gipperkid

[Mopar1973Man]

11 hours ago, gipperkid said:

Only codes the scanner was able to pull were P0216 and P0230. Also before swapping batteries I could key on and get the brief second of the lift pump and wait to start until the grid heater kicked off.

 

Just remember the batteries can be disconnect for YEARS and still store the error codes. Disconnecting batteries only reset the APPS position limits in the ECM. So APPS relearn needs to be done.

 

11 hours ago, gipperkid said:

I get the truck in the garage and I notice I have no throttle when I press the pedal. It comes and goes, then the truck starts to lope and then just shuts down. And now the WTS is flashing again.

 

ECM failure I'm almost sure of it.

[Hawkez]

 

 

 

[gipperkid]

23 minutes ago, Mopar1973Man said:

 

Just remember the batteries can be disconnect for YEARS and still store the error codes. Disconnecting batteries only reset the APPS position limits in the ECM. So APPS relearn needs to be done.

I'm going to borrow a co-workers Snap-On Solus scanner. It should be able to "see" more than the basic BluePoint scanner I used last night. I swapped batteries one at a time, started with passenger battery first. Not sure if that made a difference. The old batteries still had charge, but dropped when load tested. Being almost 9 years old I'm sure they exceeded there time.

Just now, Hawkez said:

 

 

 

I've had the P0216 code for a hwile, I'd say a year at least. Not sure if the P0230 appeared because of the no-start with the flashing WTS.