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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
Starter has been getting weak for quite a while now. At this point it just clicks like a battery that is too weak to start.
first, I knew the battery was marginal, so I replaced that.
Second, pulled the starter and opened it up, there was damage to the rotor, so I replaced the starter. Still the problem is the same. I have also swapped the crank relay with the AC relay.
Third, I bought a pigtail for the signal wire and when I connect it to 12v, starter spins fine.
So I know it's a signal problem.
Does anyone have recommendations at this point?
My plan next is to go to my friends shop and track the wire back with alldata, unless someone here can save me some time.
Could I have any of these problems ? Other relays? Ignition switch? Computer? Some other control module?
i don't know much about that switch, do you have any insight on testing it? I would hate to just throw parts at it
You might want to start some research on how they fail. Sound like the most reasonable suspect of power is not making it to the starter and all the wires are in good shape.
after looking at the diagrams, I think I am going to change out the crank relay that is in the BCM before I start replacing wires.
Before I swapped the relays in the under hood fuse box and hadn't done anything with the one on the BCM
Yeah I'm starting to have the same issues these are the same issues I thought I had solved with a new Gear reduction starter and a new battery......
After 4 months it started again. It won't start sometime after not being driven for a while. .... All it will do is show a check engine light.
I can go thru a sequence of shutting the engine down and waiting until all electronics in the car has shut down. ....... Then it might
start on the 1st or 2nd time I repeat that process.
So in my case in my 2010 Z it might be a bad relay.
If you suspect it's the relay, my suggestion is to simply disconnect it and hook it back up several times before you buy a replacement. It may be just oxidation that has gotten worse over the months/years.
First thing to do is prove WHERE the fault exists.
Take a look at the attached foto - the relay with starter written on it is the one applying full battery volts to operate the starter solenoid which applies battery to the starter.
ENSURE car is out of gear.
Remove this relay, carefully pop off the plastic cover, and re plug-in the bare relay with cover removed. Then manually press the relay armature with finger. The starter should crank but engine will not start. If it doesn't crank at full speed then fault is something between the relay contacts and starter or faulty starter or earthing - then with voltmeter prove where fault is. If it cranks perfectly then fault is further back towards start button etc. Just follow the circuitry back if necessary - but usually the problem is within the starter area itself.
My relay is modified with a manual over ride button so I can crank engine without removing relay cover etc but the operational principle is exactly the same.
And if the problem is relay contacts DO NOT use emery paper on contacts as it severely damages contacts causing future problems.
i thought it might be a bad ground, so I used a jumper cable to ground the starter directly to the bat with no luck. Also tried from frame to block. I think I need to still check the ground buss in the fuse box.
First thing to do is prove WHERE the fault exists.
Take a look at the attached foto - the relay with starter written on it is the one applying full battery volts to operate the starter solenoid which applies battery to the starter.
ENSURE car is out of gear.
Remove this relay, carefully pop off the plastic cover, and re plug-in the bare relay with cover removed. Then manually press the relay armature with finger. The starter should crank but engine will not start. If it doesn't crank at full speed then fault is something between the relay contacts and starter or faulty starter or earthing - then with voltmeter prove where fault is. If it cranks perfectly then fault is further back towards start button etc. Just follow the circuitry back if necessary - but usually the problem is within the starter area itself.
My relay is modified with a manual over ride button so I can crank engine without removing relay cover etc but the operational principle is exactly the same.
And if the problem is relay contacts DO NOT use emery paper on contacts as it severely damages contacts causing future problems.
this sounds like a good step. I was goin to pull the relay and jump the contacts directly, but this will give me an idea of the condition of the contacts. I think I will also have someone push the start button with the cover off and I can observe if the contacts stay locked in or not.
Thanks, all good info.
i thought it might be a bad ground, so I used a jumper cable to ground the starter directly to the bat with no luck. Also tried from frame to block. I think I need to still check the ground buss in the fuse box.
Ok, doesnt sound like a grounding issue, but, if i were to guess, id say that a slow crank would fall victim from the larger gauge wire paths, battery to starter. How does the large red wire/terminal look at starter solenoid? Lotta heat down there.
Ok, doesnt sound like a grounding issue, but, if i were to guess, id say that a slow crank would fall victim from the larger gauge wire paths, battery to starter. How does the large red wire/terminal look at starter solenoid? Lotta heat down there.
its not really a slow crank, the solinoid engages and disengages rapidly over and over when the start button is pushed in. Click,click,click,click
its not really a slow crank, the solinoid engages and disengages rapidly over and over when the start button is pushed in. Click,click,click,click
That actually sounds like the hold winding in the solenoid is faulty assuming the battery voltage is adequate.
Measure the voltage on the starter solenoid (schematic 2 terminal 1) which I sent. It must be up around 12 volts coming from the relay. And yes access is a PIA.
If you look at the circuit, battery from the start relay pulls in the solenoid on the left hand coil operating winding and the hold winding on the right hand side should hold the solenoid operated because the solenoid contacts bridge out the left hand operating coil when the solenoid operates. This is done to reduce current drain from the solenoid and hence heat generation.
If the solenoid is clicking then the only way that can happen is if the volts on terminal 1 drop below hold voltage (possibly around 8-9 volts on terminal 1) or alternatively the hold coil is faulty (maybe hold wire not soldered on terminal etc).
In other words if the volts on terminal 1 is holding up around 12 volts then you almost certainly have a solenoid fault.
I bought a pigtail for the signal wire and when I connect it to 12v, starter spins fine.
.
That eliminates most of what other are recommending here.
So I know it's a signal problem.
Then check your clutch switch with an ohms meter.
If that is OK then your ign switch is generally the only other fail point.
SO what you should be doing is taking the 12v signal lead of the starter and check it with a volt meter and I bet it just goes nuts with readings from zero to 12v quickly.
That actually sounds like the hold winding in the solenoid is faulty assuming the battery voltage is adequate.
Measure the voltage on the starter solenoid (schematic 2 terminal 1) which I sent. It must be up around 12 volts coming from the relay. And yes access is a PIA.
If you look at the circuit, battery from the start relay pulls in the solenoid on the left hand coil operating winding and the hold winding on the right hand side should hold the solenoid operated because the solenoid contacts bridge out the left hand operating coil when the solenoid operates. This is done to reduce current drain from the solenoid and hence heat generation.
If the solenoid is clicking then the only way that can happen is if the volts on terminal 1 drop below hold voltage (possibly around 8-9 volts on terminal 1) or alternatively the hold coil is faulty (maybe hold wire not soldered on terminal etc).
In other words if the volts on terminal 1 is holding up around 12 volts then you almost certainly have a solenoid fault.
i just pulled the cover off of the relay, and when pushing the contacts in manually, it spins the engine instantly and keeps going. So the relay is dropping out. I have tried swapping out this relay with another one in the fuse box that looks the same (AC I think) with no luck. So now I am worried about it being the BCM. I will bring home my fluke DMM tomorrow and see what the relay activation Voltage is. After that, I have to disassemble the fuse box and track the wires back to the BCM and look for a short?
Everything else the BCM controls seams fine.
03-15-2017, 10:21 PM
Starting issue
