Archived No TACH, not CHARGING, irratic LOCKUP

[robbiesworld]

Hi guys,

Yesterday my TACHOMETER quit working and my tourque converter was falling out of lockup very easily. Last night I noticed my alternator was not charging. Any help would be GREAT! Thanks.



It's sitting in my driveway with dead batteries and I don't want to put an alternator on it if that's not the problem.



1995 CUMMINS 4X4 X-CAB AUTO

 

[JoeBioDiesel]

Do a quick search. I bet you'll find that your crank sensor is bad. Lot's of posts about figuring it out.

Most guys simply replace them because they don't have a meter that can test them.



Joe

 

[raychem]

Hi guys,

Yesterday my TACHOMETER quit working and my tourque converter was falling out of lockup very easily. Last night I noticed my alternator was not charging. Any help would be GREAT! Thanks.



It's sitting in my driveway with dead batteries and I don't want to put an alternator on it if that's not the problem.



1995 CUMMINS 4X4 X-CAB AUTO

Like JoeBioDiesel said. Check the spacing on the front crank sensor... it should be about . 050 thousanths plus or minus . 005. Worst case senario is a bad PCM. Search under PCM and 2nd gen forums; lots of answers. Check the crank sensor first though.



Richard

 

[AWeis]

check your tps senser it can raise hell like yours goodluck

 

[robbiesworld]

Do a quick search. I bet you'll find that your crank sensor is bad. Lot's of posts about figuring it out.

Most guys simply replace them because they don't have a meter that can test them.



Joe

Will the crank sensor failing cause the charging failure, or maybe the alternator went bad and caused the crank sensor to go bad? what other purpose does the crank sensor serve?

Thanks

 

[JoeBioDiesel]

Like every sensor on the truck, it tells the PCM information that's critical for operation. The crankshaft sensor tells the PCM that the engine is running. It has no other way of knowing that on a 12V. It won't set a code. The reason that it can cause the symptoms you have is this:

The PCM won't try to charge the battery if the engine isn't running, right? It wouldn't make sense to try.

If it sees 0 RPMs it won't try to lock the converter, or shift to 4th gear either.

A failing alternator cannot hurt a crank sensor.

Joe

 

[LandShark]

When the crank position sensor (proper name for this is 'engine speed sensor') is bad the following will not work:
tach
overdrive
torque converter lockup
cruise control
alternator

Does the 'wait to start' light work normally?
I went through this last year. Do a search on my user name. Turns out I had a failing alternator which spiked the voltage, which caused the PCM to fail, and caused a corroded +12v PCM supply wire to fail.

There is not much to go wrong with a engine speed sensor unless it gets physically damaged. It's just a magnetic pickup.

What codes did you get from the PCM?

 

[Missouri Mule]

The engine speed sensor connector if dirty or has bent/loose pins will cause your problems. Of course a bad engine speed sensor will cause them also.



The ESS signal is a input to the ASD relay which sends line voltage to the EVR located in the PCM which determines the voltage output of the Alternator.

The ESS signal is used for other components as mentioned.

 

[robbiesworld]

Ok I took my ESS of last night and cleaned/ inspected it very well. It looked good and the three prong plug was beautiful. Alll wires were nice and not bare. It stuck to a piece of metal, so the magnet is good.



I charged the batteries and checked the following things.



I have overdrive

I have tourqe converter lockup (althought it doesn't hold in properly)

I have cruise control

I DO NOT have tachometer

I DO NOT have any charging.



My buddy scanned and it said the PCM was not getting a signal from the ESS

 

[robbiesworld]

The engine speed sensor connector if dirty or has bent/loose pins will cause your problems. Of course a bad engine speed sensor will cause them also.



The ESS signal is a input to the ASD relay which sends line voltage to the EVR located in the PCM which determines the voltage output of the Alternator.

The ESS signal is used for other components as mentioned.

So could the ASD relay go bad and cause this? or just the EVR go bad?

 

[Missouri Mule]

Yes the EVR (electronic voltage regulator) has been known to go bad but since your ESS is not sending a signal to the PCM you need to find out why.



Are you getting voltage to the ESS ( it should recieve 5 volts from PCM)?



Do you have a ground? One of the three wires is a ground wire if not getting ground you need to add a remote ground wire.



power wire=violet/white

ground wire= black/light blue

signal wire= gray/black

 

[AABEN]

All so check all ground wires! Remove and clean all ground wires bad ground will give the brain box fits. check at all points frame and fire wall-----GOOD LUCK

 

[robbiesworld]

Yes the EVR (electronic voltage regulator) has been known to go bad but since your ESS is not sending a signal to the PCM you need to find out why.



Are you getting voltage to the ESS ( it should recieve 5 volts from PCM)?



Do you have a ground? One of the three wires is a ground wire if not getting ground you need to add a remote ground wire.



power wire=violet/white

ground wire= black/light blue

signal wire= gray/black

Ok so if i check the violet/white I should get 5 volts and if I make sure the black/light blue wire is grounded, will the gray/black wire throw any kind of voltage to check?

 

[LandShark]

Can you give us the actual PCM codes? Do the key on-off routine to get the codes.

The torque converter will not lock, the overdrive will not work and the cruise control wil not work unless there is a signal from the ESS. Therefore the ESS is OK.

Is the 'wait to start' light working normally?

Where are you located? I have a spare ESS.

 

[robbiesworld]

Can you give us the actual PCM codes? Do the key on-off routine to get the codes.



The torque converter will not lock, the overdrive will not work and the cruise control wil not work unless there is a signal from the ESS. Therefore the ESS is OK.



Is the 'wait to start' light working normally?



Where are you located? I have a spare ESS.

Hey Thanks I am in Chico Ca. Northern Ca. About 3 hours from Oregon. I was kinda hoping it is the ESS because it's easy to replace. I am going to unplug it and see how it acts.



My wait to start light comes on with the other lights but does not stay on any longer than the other two lights. (normal ignition cycle of a few seconds) although I have not tried it under 60 degrees.



As far as codes my friend just read the snap on scanner but I will go hook it up and try to figure out how to use it because he left it with me to use.

THANKS!

 

[robbiesworld]

WELL CRAP!



I just went outside and unplugged the ESS up un front of the head with the round connector and three prongs.



With the ESS unplugged I HAVE Overdrive I have Cruise Control and I have Lockup although lockup will easily fall out with moderate accelerator pressure. I can hold it in lockup if I roll the throttle harder and harder.



basically nothing changes???????



I am stumped



Should my wait to start light stay on for a while even if the truck is hot?

 

[LandShark]

I asked about the wait to start light because abnormal operation (flashing) is a good indicator that the PCM is likely toast. I'm leaning in that direction anyway since what you are seeing makes no sense.

You can get codes by switching the key on-off-on-off-on within 3 seconds and counting the MIL flashing.

 

[robbiesworld]

I asked about the wait to start light because abnormal operation (flashing) is a good indicator that the PCM is likely toast. I'm leaning in that direction anyway since what you are seeing makes no sense.



You can get codes by switching the key on-off-on-off-on within 3 seconds and counting the MIL flashing.

The wait to start light has not been doing any flashing. I plugged my ESS back in and started the truck shut it off and tried the on off on off on thing and it showed no flashing. I tried this a few times with no luck.



I know this is getting rediculous. Thanks for hanging in there and helping me fiqure this out!

That kinda sounds like I solved my problem, I still have no clue what the heck is wrong with my truck

 

[LandShark]

The fact that you can't get any codes points to a computer failure. At the very least you should get a code 55, which means 'code checking complete'.

 

[Missouri Mule]

You should try the scanner and see if you get codes off the PCM.



With the engine off I doubt that the ESS will send any signals to the PCM.

Engine would have to be running to have a signal sent. If you think you can do it without injuring yourself go for it ( see if it is sending a signal). The voltage should not be more than 5 volts.



As LandShark states the PCM mite be the problem.