jeff48

Hi everyone

Here is the latest update---Battery fully charged


1. All fuses operate normally.
2. No difference in voltage readings when Phoenix Fuse, block and mounting are out of the system. Still about 12.8 in Keyoff position and around 10.6 with key in the ON position.
3. **New test** (I have never tested this before this morning)== 12.8 Key OFF and 12.6 Key ACC----Hmmm doesn't seem to be an accessory drain.

4. Rockon---> I tested the Interlock switch at the clutch pedal and it tested OK according to FSM procedures.

5. Gideon----->"Did the car get hit by lightning lately?" Nope but it could happen soon....

6. Jodeny-----> I haven't got into the under car stuff yet but I am going to try your suggestion first time under the car.

7. Last thing will be to pull the ignition switch and test it.


So everyone knows, the car will not start with a jump, it acts identically to the way it acts without the external power.

I put everything back together and popstarted the car and she fired right up. Took her for a drive and the PFC Commader shows 14.6-14.8 Volts which is a little high for my car, but seemingly within limits. When idling at about 1000 RPM, both the Commander and the DVOM at the battery show about 13.1-13.6 volts.

One horribly nasty thought keeps occuring to me, Please someone tell me there is no possibility that the Power FC ECU can't be causing my problem----------PLEASE!

InsaneGideon

But the battery keeps a solid 12.8 in all cases? And you got 0V across (explicitly) the phoenix fuse?

jeff48

Yes, regardless of what shows on the Commander or at the fuseblock the battery shows the same reading as it does in the Key OFF position.


Yup, hooked up the + probe of the DVOM to the + side of the battery and the - probe to the output side of the actual fuse (cable running to the underhood fuse block) and got 0.00 Volts. I also took the fuse out of the system completely.

mad_7tist

see what the volatges are going into and out of the clutch switch when you are cranking it. there are 2 switches one is for the starter one is for the ecu. when the car is cranked you should get batt voltage to the s terminal on the starter. sorry if i am re-itterating stuff i just thumbed through the posts.

InsaneGideon

Sorry, I should've asked this earlier: was that 0V across the fuse gathered while the ECU/fuse block is giving you the ~9v figure? ...Just so I don't miss any fine details.

If so, try disconnecting the starter from that main fuse / battery lead conglomerate...see if your 3V comes back. Which reminds me, which underhood fuseblock are you measuring at? The main one with the OEM battery terminal or the larger one with a few relays? You may want to inspect these and their wiring in more detail with the meter. There might be an OEM wire hanging by a strand.

jeff48

Thanks for sticking with me through this.
Yup. the 0v occured when the ECU/fuseblock was giving the low figure.

I will check all this today.



That is the plan for later today. Thanks for the response.

jeff48

Okay folks---here are the latest results from the undercar excursion

All wires are in great shape and NO oil residue is found anywhere. Nice clean underside of the FD

These are the results for each and every change in variables listed below as A,B, C. . . .

AT battery ~12.1 whether switch is in OFF/ACC/or ON position
AT underhood fuse block--~12+-.1 when switch is in OFF or ACC position ~10.6 when switch is in ON position
Reported by Power FC Commander-->~10.6 when switch is in ON position

A. Remove the signal wire from the solenoid
B. Replace signal wire remove connection wire between solenoid and starter
C. remove signal wire and connection wire between solenoid and starter
D. Remove +12v connection to solenoid. replace signal wire and connection wire between solenoid and starter
E. Leave +12v connection disconnected, reattach signal wire
F. Leave +12v connection disconnected, reattach signal wire and connection wire between solenoid and starter
G. disconnect ALL connections.

Voltage loss appears unrelated to starter or solenoid.

Really doesn't leave much but the ignition switch does it.???????

LUPE

sounds like the ignition switch..... hot wire it.

i'm sure you've tried the screw driver/starter trick to rule that out.

jeff48

Hey LUPE

Can't hot wire it.... I grew up in the suburbs and never learned the survivor skills needed to survive in the inner city.

Actually I did not try the screwdriver trick....can you describe it for me?


To everybody

I just got beack from another undercar excursion. This time to check the output to the "S" wire on the starter.

Key Off----->0 Volts
Key ACC-----> 0 Volts
Key ON------->0 Volts
Key START---->3.3 Volts

That doesn't seem right.

I am starting to agree with LUPE and DALE CLARK that the ignition switch or the signal wire circuit may have failed.

Just for grins I also disconnected the 12+ cable from the battery to the underhood fuse box at the large box (the one with the BIG fuses) and, as I expected, the voltage remained the same as the battery regardless of the switch position.....SO it is starting to look like there is a low amperage voltage drain at the fuseblock that somehow is not affecting battery voltage......????????

Gadd

My money is on a bad ground. I know you checked with a ohm meter but that was with no load. When your checking the bat. voltage, are you testing directly on the bat. terminal?
Try testing voltage from the +bat terminal and a few body ground points, and on the motor with the key in the ON position.

LUPE

Simply lay a screwdriver ( metal shaft ) across the 12v nut to the ground nut on the backside of the starter. You'll know if you've got power and a good starter by doing that and be ready for some sparks

mad_7tist

that is why i said to chek the voltage on the starter interlock switch on the clutch. it should see 12v going into it from the ignition switch. then 12v going out to the the s terminal. if not battery voltage than you have a drop at the switch. lupe's way will work just be sure the car is out of gear. prob the easiest. but you know the 3.3 volts is the prob. the solenoid needs ~11v to engage.

jeff48

Starter interlock should show 12V going into the interlock by the Bl/Y wire when the ignition switch is in the start position, it is actually only carrying the 10.6 voltage that other systems show in the ON position. The switch checks out perfectly and transmits full voltage out as it receives.

There are only two remaining components----ignition switch and the security system (including the starter cut relay).

mad_7tist

here is the thing if the voltage coming out of the switch is ~10.5 volts and the voltage at the s terminal on the starter is ~3v then you have a problem with the starter wiring. that wire coming out of the starter switch goes to the solenoid. i was not stating that to check the switch but to check the ignition switch. that signal coming out of the starter interlock switch goes to the starter cut relay and any aftermarket alarm you have follow the wire and check the voltage before and after the relays again.

InsaneGideon

Yeah, I agree w/Gadd. Time to secondguess ground connections under load.

Put the car on "ON' place one Vom - lead directly on the battery negative, place the + on the engine "block". Should be nearly 0... Rule out bad engine-battery ground.

When you measured the fuseblock voltages, where was the VoM negative probe at?

Under these same conditions, what happens to this voltage when you put your high beams on?

jeff48

OK now we are seeing something unexpected. With the switch in the ON position and the - probe on the battery negative and the + on the engine block, or just about any other ground point I read ~ 1.35 volts......when highbeams go on I read ~ 4.00 Volts DC.

The question remains-----Where is the voltage coming from?

Gadd

You have a BAD ground! clean all ground points you can find.

your reading the voltage across a resistor (the bad ground )

mad_7tist

gadd is right that is a grounding problem. now i know you checked them but give them a good check out

jeff48

OK

I am going to do that tonite. I am going to check all grounds and also fit additional secondary grounds where I can. This whole grounding thing is confusing to me since I have exceptionally good grounding straps everywhere on the car, but I will try it out.....what have I got to lose?

mad_7tist

the majorly important one is the one coming off the batt, and the one on the driver's side engine block

jeff48

Thanks for the direction, I will let you know what happens

jeff48

Okay Boys You will not believe this------->

I just spent the last 1 1/2 hours cleaning EVERY single ground point on the car. NO CHANGE still 10.2v with the key in the ON position and worse with the lights on............

Jeff is ready to set fire to the car-----but holds his breath and attaches a clamp of one end of a set of jumper cables to the Negative pole of the battery and attaches the corresponding clamp on other end of the jumper cable to the UIM...I got inside and turn the key to ON....Wow, youse guys must be right there IS a ground problem, but HOW, I just checked everything. At least now the Commander is reading 12.0 with the Key ON and 11.7 with the lights on HIGH.. Now she starts. But I still have a problem, where is the bad connection and why did it go bad.

Rewind to 2 1/2 years ago.
The battery was relocated in the rear hatch area with the 12v+ run through the Phoenix 150 and through the cabin into the engine compartment where it attached to the Main Fuse block... The Negative cable was routed from the battery to the passenger side rear strut tower where there are three strut nuts holding the strut to the tower. The nut closest to the passenger seat was removed and the manufactured end was attached to the stud and tightened. There it sat for 2 1/2 years with no problems. UNTIL THIS

With the negative battery lead still attached to the strut tower and the jumper cable end attached to another strut nut I can transfer ground to the UIM with no problem. But as soon as I try to simply transfer the ground through the strut tower connection (no direct connection to the UIM) I get nothing. Then I figure the battery cable is degraded so I take one end of the jumper cables and attach it directly to the negative battery pole and the other end to the strut tower nut. Guess what----Lousy ground 10.6 with the key in the ON position. Now I am really confused and I try the other strut tower nuts------NOTHING.

Finally I connect the jumper to the negative battery pole and just about any other metal surface on the car and I have 12.0 volts with the Key in the ON position and 11.7 with the lights on high. In other words---no problem except when I try to use the connection I have used for 2 ½ years. In case you are wondering, I cleaned the strut tower nuts and connectors......

Can anyone diagnose why the connection that had been perfect for so many years, now chooses to fail completely and what I can do about it?

DaleClark

iTrader: (55)

That connection is through paint and isn't the best. Hard to say exactly *why* it degraded, but it's a really good idea to have a good, solid connection from the negative terminal to bare metal. If it's in the storage bin, you could even use one of the unused bolt holes for the rear seat seatbelts. Scrape the paint off with a wire wheel and bolt the cable down.

I've never relocated a battery (stock location works fine for me ) but the factory harness grounds both the frame and the engine. Might want to add a cable from the battery's chassis ground to the engine - that's the best way to do it, IMHO.

Dale

LUPE

HOORAY!

Jeff is going to the Revolution now!!!

I'll start collection liquor!

jeff48

Maybe no......Sharon just informed me that her Mom's 80th birthday party is Sunday. Maybe a Friday-Saturday trip is possible...........