This is an 07 Dodge 4door PU, [diesel], no OEM alarm.

The alarm/remote start is an UltraStart and the bypass mod. is the Fortin PATS-CHRYSLER-04+.

Everything works except starter continues to crank after engin starts, [output from remote start starter lead stays live].

This truck does not have a start wire at ign. switch, start output lead, [from remote start] is connected to the bypass mod.

Yes we have tried replacing the remote start and bypass mod, same result.

I think the problem is no tach signal, [system acting like there is no tach signal] I have tried all recommended locations for diesel tach signal, the UltraStarts site, WireMagic and 12V.com all give it as dark blue/gray at pin #24 of 60 pin plug at ECM on drivers side of engine, 12volt also indicates it is also available at the CPS, [just to the left of ECM]

Pin 24 is not a dark blue/gray, it is purple/white, [there is no dark blue/gray on 60 pin plug] and is not a tach signal, the dark blue/gray at CPS is also not a tach signal, looks like it is a 5V referance lead.

We have also tried both the wired tach and "tachless", [voltage sensing] modes and both program as if system is "seeing" tach or voltage increase, [UltaStarts do not go into remote start mode if tach or tachless is not programed].

System will work on "stop and go" feature, [press remote start then turn ign. switch off to keep engine running] and if I disconnect starter lead once engine has started, there is still power on starter output lead for 5 sec., [max crank cycle for UltraStart] but engine shuts down after about 9 sec. and no shutdown diagnostic.

Both Fortin and UltraStart tech supports are stumped.

Unfortunately the customer ran out of time so I could not do any more testing, he will be gone for a month before the truck comes back, [for 3rd time, all day yesterday and from 7:30 this morning till 12:00 noon today]
This is one of those customers we all want, although disappointed both yesterday and today he was more concerned about how much time we had to spend on his truck, even though he new it was not going to cost him any more, his parting words today where "no big deal, **** happens, see you in a month"
Needless to say I want to help this guy out, customers like him are hard to come by.
Any insight to this problem would be greatly appreciated, TIA.94

 

I wish I could help. I can't, but I just wanted to remark on this historical Honda-Tech event. It's fcm's first thread created EVER on this forum. 14,000 posts that were all replies.

Have you tried directech? Pretend like it's a DEI alarm.

 

I won't be able to help until mon (on vacation)- no access to tech support,

 

The reason for most remote starters to keep trying to crank the car is low or no tach reference. Is there a way to program the unit for low tach pick up? Also can you program the unit for no tach sence and use a timed crank mode? Also can you grab a tach sence at the fuel injector? I done a non desiel verson of the truck. I'll try to help you out in any way.

 

As I mentioned I also believe it is a tach issue as the system is in one sense acting like there is no tach signal, [cranking after starting] on the other hand tach programs in both tach mode, [hard wired tach signal source] and tachless mode, [current sensing].

All wiring sources give tach source for the 07 Dodge Ram 3500 diesel as the dark blue/gray at ECM/ECU low on drivers side, pin 24 on 60 pin harness, Directech and 12V.com indicates it can also be found at the CPS just to the left of ECM/ECU, [3 wire plug].

Heres the rub, there is no dark blue/gray at the ECM/ECU, on either plug and pin 24 of 60pin plug is violet/white, and even though UltraStart tech support and Fortin tech support says to use it no matter what color it is, pin 24 is not a tach signal, or is the dark blue/gray at the CPS, my "tach tester" says they are not, yet the system programs tach using either one of the leads, UltraStarts do not program tach unless there is a tach signal, [or are not supposed to] so you can see why it has myself and UltraStart and Fortin tech support confused.

Yes, we have already switched both the UltraStart brain, the Fortin bypass module, checked the wiring, checked wiring continuity, tried tachless mode, apparently this will not work on 07 or later Dodge Ram PUs and many other 07 and newer vehicles as the ECU "controlled" voltage regulator is not "turned on" until 5-7 seconds after engine starts, so no voltage increase for 5-7 sec., tachless will program, [locks in] as programing is done once engine is running and the 5-7 sec. has elapsed.

Yes UltraStart has adjustable tach signal "strength" and it has been tried.

I have figured out that there must be a "pulse" from the CPS, [just not the dark blue/gray lead] and I will check the other two leads when the truck is back in Oct.

There must also be a "tach signal", just not pin 24 of 60 pin plug at ECM/ECU.

I have never tried, [and did not know you could] using an injector on a diesel for a tach signal, hmmmm?

Last resort is a pulse generator. 94

 

we had the same issues with a buddies 2007 3500 mega cab. It's been a couple of years but I think it had something to do with putting a resistor on the start wire of the bypass. Sorry I couldn't be more help but I hope this refreshes someones memory. Good Luck

 

fcm, is there no way to turn engine sensing off alltogether like the dei systems(no voltage or tach sense)? if so it may not look for any input and just run the crank output from a predetermined crank time. all i ever do is dei so im probably no help at all. good luck though.

 

No, UltraStart remote start systems need tach learned, either tach or tach-less, [current sensing] or remote start will not work, there is a crank duration adjustment but it works by increasing or decreasing the tach sensitivity, and works great if tach is programed. 94

 

Is it possible to just wire the tach sensor to a different voltage that goes hot when the engine is started?

 

For tach-less, [current sensing] the tach sensing lead from the remote starter is not and can not be connected to anything, programing tach-less is not possible if the tach lead is connected to anything, even ground.

We know the tach-less mode works, when programed properly, because the UltraStart will go into "stop and go", [press remote start, then turn ign. off, to keep engine running.

If tach is lost or alt. failed, [when in tach-less mode] the UltraStart will not start the engine or keep the engine running in stop and go mode, so we know the system works.

As mentioned, on the 07 Dodge Ram 3500 diesel the trucks ECU/ECM does not turn the alt. "on" for 5 - 7 seconds, so the remote start does not "see" the voltage increase even though engine has started and continues the output for starter, ugly sound, when in stop and go mode engine is already running so it "sees" the voltage increase keeping the engine running.

For tach mode the tach lead must be connected to a ((((pulsed)))) source, any pulse tied to engines RPM, or tach can not be programed properly.

So the question is still... where is tach signal on the 07 Dodge Ram 3500 diesel?
I am more convinced then ever, [or hoping] that the problem will be solved once I find a tach, [pulse] signal strong enough to be programed into the unit.94

 

so the camshaft position sensor or ECM on the firewall wouldn't provide a tach signal. We used to also have to rev the motor up a little on jeeps to program tach for DEI remote starts.

 

have you tried using a D.E.I. 454T? as long as it senses a voltage it should give you a tach output.. i would not go out and buy one but if you had one at your shop that would be cool... we keep these around at my shop.

 

The ECM/ECU is mounted to the engine, drivers side on the diesel, it is where all the wiring guides say tach signal is, [dark blue/gray pin 24 of 60 pin plug], the problem is pin 24 is not a dark blue/gray, it is violet/white and is not a tach signal.
If it was a gas engine tach is at the PCM in engine bay on pass. side firewall, dark blue/gray lead second plug down, on diesel engine model the PCM is there but it has no second plug down.
The CPS may also work, where is it and what color is the wire?94

 

as a last resort we will use a "pulse generator" like the DEI 454T. 94

 

the crank position sensor is just left of the ecm in a 3 pin plug. sorry no wire color listed

 

Wait, say what??
You said, "camshaft position sensor", where is it located?

I know about the Crank Position Sensor, it is mentioned as another possible location to get "tach" signal in some wiring guides, however the dark blue/gray at CPS is not "tach" it is 5V reference.

When truck comes back, [mid Oct] I will check the other two leads at the CPS to see if the pulse, [one of them must be a pulse] is strong enough to program into remote start.

If there is a Camshaft Position Sensor my question would still be, where is it, as it would also be a possible location to get a tach signal. 94

 

sorry 2 things running through my mind at once crank sensor

 

FCM how are you measuring your 5v reference?

The tach signal is a pulse. If measured with a DMM it will just read 5v. You need to switch it to frequency and see if you get a reading. The frequency should change with the change in rpm.

You should try probing around a little more.

 

By frequency I think you mean AC instead of DC. Also I don't know what a 'tach tester' is, but just make sure your multimeter is set to measure AC.

 

Depending on the DMM AC will only show volts. Frequency will show obviously the frequency of the signal in hertz. Even at AC all you will see is a 5 volt signal. You will not see the frequency of that signal. A 5 volt signal at 60hertz and 1khz will look the same on the AC setting they will both read 5 volts.

New Tachs are not analog they are usually a digital pulse that varies in frequency.

 

The "tach tester" is Command Starts tach signal finder, a handy little tool, it will tell me if I have a pulse, how strong the pulse is and if it is 1-10 cylinder, [for old school remote starts that number of cylinders has to be programed before tach will program].

I Googled CPS, [wiring] for 07 Dodge diesel, that is how I found out the dark blue/gray is the 5V reference lead and at the same time found out the brown/white is the signal, this was of coarse after truck had been buttoned up as customer needed it, I will use the tach tester on the brown/white at the CPS once the truck comes back, to see if the signal is strong enough to program as tach.

At this point all I am asking is if anybody else has done, [remote start] an 07 Dodge Ram 3500 diesel and where they found tach, if I have to I will probe all 110 leads on the ECU/ECM until I find a strong enough pulse to program into the remote start as tach. 94

 

Can you just go to a parts store flip through a repair manual and look in the back of the book. Almost all have detailed electrical drawings.