I just got the new Powermaster unit up and running and got the car started and it runs great but I'm only registering 11.80 volts at idle when normally it was 14.1. I had correct voltage only a week ago BEFORE the A/C compressor and Powermaster units where changed. I don't have the A/C compressor connectors hooked up right now because the system is not charged and I don't want to kill the new compressor by it kicking on. I put a voltmeter on the alternator while the car was running and it was showing 11.80. I'm losing a charge somewhere but don't have the slightest clue. The battery is an Optima which is new and the alternator is a new 120 amp unit. I also checked voltage at my Caspers positive cable junction box where all the fusible links go and it shows 11.80 as well. Any ideas? If it isn't one thing it's another!
The never ending saga...now the car is only running at 11.80 volts
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mikestertwo
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Does the voltage go up when you bring the rpm up? Are you running an underdrive crank pulley?
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is the volt lamp lit with key in on position ?
recently had one that had a loose bulb and you need to have the bulb operable to excite the alternator
recently had one that had a loose bulb and you need to have the bulb operable to excite the alternator
I have a GNX dash and have bypassed the idiot light setup. I have Casper's field fix harness which allows me to draw voltage to the alternator from the Boost control solenoid (that's the ONLY thing I use that stupid thing for!).
Battery and alternator are both showing 12.15 Volts just sitting with key off.
I guess since I essentially changed NOTHING other than the powermaster and A/C compressor since I last had 14 volts...how do you check for a bad alternator even though this thing is like brand new??? My car will run on my Optima battery for like 50 miles before it gives out (trust me I've done it before on accident!).
Battery and alternator are both showing 12.15 Volts just sitting with key off.
I guess since I essentially changed NOTHING other than the powermaster and A/C compressor since I last had 14 volts...how do you check for a bad alternator even though this thing is like brand new??? My car will run on my Optima battery for like 50 miles before it gives out (trust me I've done it before on accident!).
chopped39
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Make sure the dash connections are good. My digital dash had bad connection and caused same problem. That was after buick installed new alternator and battery under warranty.
Well I just tested the connector that goes to the alternator with the key on (field fix harness) and one of the terminals shows 0.04 while the others show nothing...is this a normal reading? I wouldn't think so? maybe the boost solenoid is shot? I don't use the boost solenoid for anything but this field fix harness...I don't use it for boost control
salvageV6
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Check the ECM/SOL fuse.
You probably shorted the circuit changing out the compressor.
If it blows again, check the plug on the compressor for the diode in it could be twisted up shorting out the circuit.
Should get +12 on the pink/blk wire at the wastegate solenoid connector key on.
You probably shorted the circuit changing out the compressor.
If it blows again, check the plug on the compressor for the diode in it could be twisted up shorting out the circuit.
Should get +12 on the pink/blk wire at the wastegate solenoid connector key on.
salvageV6
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Check for power at the other solenoids.
Such as TCC, EGR, canister purge, A/C cutout relay power, and if you don't have any, the feed comes out of C100 connector under the wiper motor.
In and out of the car it's always a pink/blk wire, it allegedly goes to the brake switch first right off the fuse panel before exiting the car out of the C100 connector, maybe it got disturbed there?
There's also a splice in the harness that feeds all the various solenoid individual wires. Check that last.
Such as TCC, EGR, canister purge, A/C cutout relay power, and if you don't have any, the feed comes out of C100 connector under the wiper motor.
In and out of the car it's always a pink/blk wire, it allegedly goes to the brake switch first right off the fuse panel before exiting the car out of the C100 connector, maybe it got disturbed there?
There's also a splice in the harness that feeds all the various solenoid individual wires. Check that last.
OK I checked the EGR connector (even though I don't run EGR anymore) and also checked the purge canister solenoid connector and no voltage on either of those with the key on (on the EGR connector, I get 11.80 volts on the brown wire terminal but nothing on the pink/blk).
Attached is a picture of what wires were cut (all wires shown that are cut went to the OEM fan relays).
What I did to get power to the Powermaster was splice into one of the red power wires from one of the old relays. The brown wire I spliced I have no idea what that goes to but it used to have some sort of "X" solder piece and two of the ends had nothing attached to them??? Talk about a mess I have created! :frown:
Attached is a picture of what wires were cut (all wires shown that are cut went to the OEM fan relays).
What I did to get power to the Powermaster was splice into one of the red power wires from one of the old relays. The brown wire I spliced I have no idea what that goes to but it used to have some sort of "X" solder piece and two of the ends had nothing attached to them??? Talk about a mess I have created! :frown:
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Again please note...this voltage problem did not start until AFTER I changed out the new A/C compressor and Powermaster unit. I had 14 volts even after I cut the OEM fan relays out. I just didn't have power going to the Powermaster pump because I didn't know that red power wire shared the same wire as one of the red power wires for one of the fan relays!!!
I just found the C100 connector diagram on GNTTYPE...I'll see if I can chase something down...
I just found the C100 connector diagram on GNTTYPE...I'll see if I can chase something down...
salvageV6
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1. Never cut wires off like that, leave the connector and tape them up below the harness, they'll stay hidden well enough.
2. Never use and trust a butt splice on your powermaster power, it may not save your butt someday. Solder and isulate them properly.
Doublecheck that ECM/SOL fuse again.
If it's good proceed over to the brake switch, it powers the lockup for the converter, output of the switch is the purple wire to the TCC should be +12 on it with key on and foot off the brake.
This is before it goes out to the C100 connector.
My guess is the powermaster install ripped a wire or two off the brake switch inside the car killing power, or the fuse is just blown.
Start the hunt inside the car. Voltmeter on both sides of the fuse to a good ground point should read +12 with the Key On for this test.
Key on readings also for the other points at the brake switch, all read to a good ground for the black meter lead. Volts scale.
2. Never use and trust a butt splice on your powermaster power, it may not save your butt someday.
Solder and isulate them properly.Doublecheck that ECM/SOL fuse again.
If it's good proceed over to the brake switch, it powers the lockup for the converter, output of the switch is the purple wire to the TCC should be +12 on it with key on and foot off the brake.
This is before it goes out to the C100 connector.
My guess is the powermaster install ripped a wire or two off the brake switch inside the car killing power, or the fuse is just blown.
Start the hunt inside the car. Voltmeter on both sides of the fuse to a good ground point should read +12 with the Key On for this test.
Key on readings also for the other points at the brake switch, all read to a good ground for the black meter lead. Volts scale.
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