93 Sable won't start - PLZ help!

[shorod]

Originally Posted by elvisload

NOTE to Rod:

Just wanted to say thanks for posting those PCM wiring diagrams!

Russ

Those diagrams are not for the PCM (Powertrain Control Module), they are for the Constant Control Relay Module (CCRM). The CCRM is mounted on the radiator core support. The PCM is mounted above the glovebox and its connector is attached under the hood on the firewall. The pinout for the two is different. If you need the pinout for the PCM, let me know and I can get it posted in the next day or two.

-Rod

[elvisload]

Rod,

My mistake...Meant to say CCRM...but would you please post the PCM diagrams as well...?... I need them.

Thanks
Russ

[shorod]

Originally Posted by jmoritz

Out of the frying pan, into the fire. I turned on the airconditioning and the compressor started intermittently buzzing loudly and emmitting a smoke like vapor. Is the compressor going out or did I do something in the wiring that caused this?

John

Hmm, if all you did was put a good ground to the CCRM, the problem with your A/C should just be coincidence. Yes, the CCRM contains the relay for the A/C compressor clutch, but the ground wire at pin 15 just connects the clutch relay coil to ground. Sounds like you either have a bad compressor clutch or a partially seized compressor and the smoke you are seeing is a slipping belt. T

he diode shown on the diagram is just to protect the solid state relay from a voltage spike when the compressor clutch disengages. If it were bad, it still shouldn't cause what you are experiencing.

Thank you for the nice comments, I'm sorry to hear you have now having other problems. It certainly doesn't sound like anything you did though. I'll check my manual to see if they list a spec on the compressor clutch coil resistance. If the windings are shorting, the resistance will likely come back low. Yep, you're going to get your money's worth out of that DMM!

-Rod

[jmoritz]

Note to whoever with similar problem: The A/C compressor wasn't going bad. It was venting pressure due to the radiator fan not working. I checked the wiring diagram and found that pin 15 ground on the CCRM is also shared by the fan. I spliced in a ground to the fan harness and everything runs just fine again.

[elvisload]

Rod,

RE: 1992 TAURUS 3.0L GL - CCRM TEST RESULTS

Got a DMM and started the tests today on the CCRM. Results as follows:

All tests done by back probing with CCRM connected.

pin 24 - red lead with black lead on pin 15 - run and start key position 12 Volts

pin 24 - red lead with black lead on battery neg - run and start key position 12 Volts

pin 12 - red lead with black lead on pin 15 - run and start key position 12 Volts

*pin 18 - black lead with red lead on battery positive - run position 12 Volts - start position Zero Volts!! (did this one several times)

pin 5 - red lead with black on battery negative - failed test - zero Volts at run and start position

The measured resistance from pin 15 to battery negative was just a few tenths of an ohm.

Battery tested at just above 12 Volts.

(All the above readings on start position were actually just slightly lower than 12 Volts, except pins 18 and 5, which were 0)


WHAT DO YOU THINK??
BAD CCRM??
SOMETHING ELSE??


THIS ALSO POSTED AT: http://www.automotiveforums.com/vbul...18#post3236618

[shorod]

Originally Posted by jmoritz

Note to whoever with similar problem: The A/C compressor wasn't going bad. It was venting pressure due to the radiator fan not working. I checked the wiring diagram and found that pin 15 ground on the CCRM is also shared by the fan. I spliced in a ground to the fan harness and everything runs just fine again.

CONGRATULATIONS! I bet that made your day! Good job. Doesn't it feel good to make such large accomplishments?!?

-Rod

[elvisload]

GUESS WHAT JOHN? I GOT MINE RUNNING TOO!


Guess what? Got it running! It was that friggin EEC TEST plug (WHICH HAD BURNT OFF). Went to salvage found one off a 92 Sable, checked to see that the wire colors matched. Spliced and soldered all 10 wires! Turned the key....VROOOM!

Apperantly the PCM or CCRM will not function without the EEC TEST plug in place. Eight of the 10 wires are in like pairs (same colors) so I'm assuming those are meant to be connected through the plug. With the plug cut off...no connection!


And Rod, I couldn't of done it without your help. I know it's extremely difficult to diagnosis without seeing the car... you probably would have made the right call within minutes of seeing the engine. But your posts here and with John's Sable led me in the right directions. Thanks a million!

Russ

[Notian]

Hey guys!

I have the same problem on a '95 Ford Taurus. I have replaced the CCRM and the PCM. I have checked to make sure power gets back to the fuel pump (which works). I can apply power directly to the CCRM and the pump goes on. I have checked the grounds for the PCM and the CCRM. If I turn the key to the "on" position, and connect and disconnect the ground to the CCRM, the pump operates, and I can start the car until it uses up the fuel in the lines. Any ideas on why the pump doesn't work when it should?

Thanks for any help! This is driving me crazy!

Nate

[shorod]

Originally Posted by Notian

Hey guys!

I have the same problem on a '95 Ford Taurus. I have replaced the CCRM and the PCM. I have checked to make sure power gets back to the fuel pump (which works). I can apply power directly to the CCRM and the pump goes on. I have checked the grounds for the PCM and the CCRM. If I turn the key to the "on" position, and connect and disconnect the ground to the CCRM, the pump operates, and I can start the car until it uses up the fuel in the lines. Any ideas on why the pump doesn't work when it should?

Thanks for any help! This is driving me crazy!

Nate

I'm don't think I'm quite following this. The fuel pump gets power and works when the CCRM is connected the way the factory did it? Or do you mean you have continuity to the fuel pump from the CCRM?

You then apply power (+12 V from battery positve?) directly to the CCRM and the fuel pump runs? Which terminals of the CCRM are you applying power to, and why if the pump works normally?

When you say you checked the grounds on the PCM and CCRM, do you mean the grounds to activate the fuel pump relay, or the actual ground to the CCRM? When you turn the key "on" which ground are you connecting, then disconnecting? The ground for the fuel pump relay, or the ground for the entire CCRM? It doesn't work with the ground wire connected, but starts working when you then disconnect the ground?

Maybe it will help me if you mention which pins of the CCRM you are grounding.

-Rod

[Notian]

Originally Posted by shorod

I'm don't think I'm quite following this. The fuel pump gets power and works when the CCRM is connected the way the factory did it? Or do you mean you have continuity to the fuel pump from the CCRM?

You then apply power (+12 V from battery positve?) directly to the CCRM and the fuel pump runs? Which terminals of the CCRM are you applying power to, and why if the pump works normally?

When you say you checked the grounds on the PCM and CCRM, do you mean the grounds to activate the fuel pump relay, or the actual ground to the CCRM? When you turn the key "on" which ground are you connecting, then disconnecting? The ground for the fuel pump relay, or the ground for the entire CCRM? It doesn't work with the ground wire connected, but starts working when you then disconnect the ground?

Maybe it will help me if you mention which pins of the CCRM you are grounding.

-Rod

Rod,
Sorry for the confusion. Let's see if I can clarify...

I took the black and green wires from the CCRM (pin 15) similar to what jmoritz did to get his going, and connected them to a good ground (previously, the termination for the ground of the CCRM to the body ground was extremely corroded, so I stipped the ends, and ran a new length of wire to a cleaned up body ground.).

When the key is turned to on, if I disconnect the green and black wire from ground, then reconnect it, the fuel pump runs. The car will start, and burn whatever fuel was injected. However, it then dies.

I got another PCM and put it in, but still no luck. I was checking all the wires to the different components and found a ground that comes off the PCM and goes to body ground right below the windshield. I unbolted it and ran it to the battery ground. Still no luck. The same thing happens. The car cranks, but won't start without me "helping" it.

At this point, I was under the impression that the fuel pump relay was a part of the CCRM. Is it possible that I have the ground for just one or the other cleaned up, but I still have a bad ground?

I should mention that one of the other ground wires I stripped and re-wired was the one that controls the cooling fan, as I can disconnect and connect it in the "on" position and have it run or not.

Thanks for taking the time to read this tome of mine. When there's more light, I will go out and confirm the pin numbers on the wires from the CCRM that I have modified, just to make sure!

[shorod]

The ground at pin 15 of the CCRM is only used for the relay that provides power to the PCM and for some of the electronic devices associated with the A/C clutch and the cooling fan. By disconnecting the ground at pin 15 you are turn off the PCM, so when you connect that ground back up, the PCM is again getting power and probably causing the fuel pump to prime the system again since the key is still on.

I would suggest backprobing pin 5 of the CCRM and watching for either light or voltage when the key is turned on after sitting overnight. If the light/meter indicates voltage for a few seconds, then your CCRM is doing what it should. If not, check for ground at pin 18 after the car has been sitting for a bit and the key is turned on. This ground would be the activation for the fuel pump relay. If you get ground here, but no corresponding voltage at pin 5, then there is a problem with the CCRM. If you have ground and power on pins 18 and 5 respectively, then you might have a problem with fuel pressure.

Since you do get some fuel pressure after cycling the wire on pin 15, the fuel pump inertia switch much be closed properly. Maybe it takes a couple cycles of the fuel pump to build up sufficient pressure in the fuel rail to allow the car to start. This could be due to a bad fuel pump, corroded wires to the fuel pump, restriction in the fuel line (in tank fuel pump screen, pinched fuel line, restricted fuel filter, or leaky pressure regulator).

If all the fuel stuff checks out, then rent a noid light set from your local parts store and make sure you injectors are all getting signal.

You may also want to pull a couple of spark plugs after trying to get the car started. If they are saturated with fuel, then you probably have plenty of fuel and not enough spark/compression.

Remember, the internal combustion engine needs fuel, air, spark, and compression in the correct quantities to start.

Good luck!
-Rod

[Notian]

Rod,

Sorry to get back so late...Gotta pay the bills! Anyway, Thanks for the response. Now that it's not raining, I'm gonna go out and do as you suggested. That whole electrical/raining thing spooks me a bit!

[Notian]

Rod,

I thought of something else if you have the patience for it. Pin 18, where should that be grounded to? In other words, I have found that because the car is so old, everything that is supposed to be grounded has needed to be buffed and cleaned. If I were to follow pin 18's wire, where in the car would it go to ulimately end up grounded?

Thanks again! You've been VERY helpful!

[shorod]

I'm on business travel this week (in sunny San Diego) and do not have my service manual CD-ROMs with me. If you can wait until this weekend or early next week, I should be able to get back to you on this. If you don't see anything from me, you may want to ping me as I probably forgot.

-Rod

[Notian]

Originally Posted by shorod

I'm on business travel this week (in sunny San Diego) and do not have my service manual CD-ROMs with me. If you can wait until this weekend or early next week, I should be able to get back to you on this. If you don't see anything from me, you may want to ping me as I probably forgot.

-Rod

No worries! Hope the trip goes well. I did go out and test, and discovered that if I disconnect the ground from the CCRM as well as the ground up under the windshield, when I turn the key to the on position, the pump runs continuously. If I reconnect any of those grounds, the pump won't operate.