My aztek has no crank when I turn the key. I have replaced the starter still no crank, took my old starter to get it checked it and was bad, took my new starter to get it checked it was good. I replaced the Ignition switch and I have checked all of my fuses and relays still have no crank anybody have any thoughts?
No crank 2001 aztek
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When a no crank comes in this is how I diagnose it.
Battery show at least 12v? If no, charge battery or replace if not good.
When turning the ignition key to the "start" position what is the battery voltage? If it drops below 10v charge the battery or replace if not good.
Okay so you turn the key to the start position and your battery voltage stays above 10v, here are the next steps.
I start at the starter motor and work backwards. There will be 3 studs on the starter solenoid which is located on the starter motor. The large stud has the large gauge battery + wire going to it which is hot at all times. The other large stud is the other side of the switch in the solenoid which will have a braided wire with no insulation usually bringing power to the starter motor when the solenoid switch is in the "closed" position or "start" position of the ignition switch. The third stud is smaller and is the trigger or signal wire telling the solenoid to close the internal switch causing power to enter the starter motor from the large gauge cable and turn the engine over.
With your voltmeter set to DC volts make sure the large stud on the starter solenoid connected to the fat battery + cable has battery voltage at all times. If there is no power repair the wire going to the battery.
Next you will need an assistant. With your meter still on DC volts probe the little stud that is supposed to get the trigger or "on" signal to start the engine. Do you have battery voltage (12v) when your assistant turns the ignition switch to the "start" position?
If you have power to the trigger stud when the ignition key is turned to the start position move your probe to the side of the solenoid switch that has the non-insulated braided wire. Is there battery voltage here when the key is turned to the start position? If no then the solenoid is bad. If all these steps check out okay then look at your engine, body, and battery grounds.
If you don't get the trigger signal to the small stud when turning ignition key to start I'll give the next steps in diagnosing the starter circuit.
Battery show at least 12v? If no, charge battery or replace if not good.
When turning the ignition key to the "start" position what is the battery voltage? If it drops below 10v charge the battery or replace if not good.
Okay so you turn the key to the start position and your battery voltage stays above 10v, here are the next steps.
I start at the starter motor and work backwards. There will be 3 studs on the starter solenoid which is located on the starter motor. The large stud has the large gauge battery + wire going to it which is hot at all times. The other large stud is the other side of the switch in the solenoid which will have a braided wire with no insulation usually bringing power to the starter motor when the solenoid switch is in the "closed" position or "start" position of the ignition switch. The third stud is smaller and is the trigger or signal wire telling the solenoid to close the internal switch causing power to enter the starter motor from the large gauge cable and turn the engine over.
With your voltmeter set to DC volts make sure the large stud on the starter solenoid connected to the fat battery + cable has battery voltage at all times. If there is no power repair the wire going to the battery.
Next you will need an assistant. With your meter still on DC volts probe the little stud that is supposed to get the trigger or "on" signal to start the engine. Do you have battery voltage (12v) when your assistant turns the ignition switch to the "start" position?
If you have power to the trigger stud when the ignition key is turned to the start position move your probe to the side of the solenoid switch that has the non-insulated braided wire. Is there battery voltage here when the key is turned to the start position? If no then the solenoid is bad. If all these steps check out okay then look at your engine, body, and battery grounds.
If you don't get the trigger signal to the small stud when turning ignition key to start I'll give the next steps in diagnosing the starter circuit.
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A strange reading, a fully charged battery is 12.75. Did you just take it off a charger when you got that reading?
I agree, 13.5v is kinda high even if just charged.
Lead acid battery has six 2.2v cells when fully charged. That comes out to 13.2v if you just pulled your battery off the charger, then typically each cell will settle down to about 2.1v each giving you a normal battery voltage reading of 12.6v. If it's been sitting for days then each cell can go down to 2.05v each giving you a total of 12.3v. I have seen batteries still last a while that after sitting for a while go down to only 12v, or 2v per cell. As long as the internal battery impedance is still low enough and starts the car easily it's not a problem.
What do I mean by "internal impedance"?
All batteries are a voltage source with a "source impedance" or also called "internal impedance" and "output impedance". All the same thing. If the internal impedance is .01 ohms and you draw 100 amps you will get a voltage drop inside the battery of 1v. This means if you have you volt meter on the battery posts and it reads 12.6v with no load, under the 100 amp load your meter will then read 11.6v since you lost 1v from the battery. This is why batteries get hot, that energy is dissipated internally. 100 amps and 1v is 100 watts of power the battery is producing into heat. Often times battery plates get sulfur built up on the plates, this increases the internal impedance of the battery which gives you less voltage across heavy loads like a starter. If the battery climbs up to an internal impedance of .05 ohms then with the same 100 amps of current you'll lose 5v. This will leave you with only 7.6v across your starter which isn't enough to crank the engine over.
This is why you need to measure the battery voltage before and during starting, if the voltage of the battery drops low while starting then the internal impedance of the battery is too high and you need to replace it. Reading battery voltage under quiescent (no load) conditions is practically pointless unless you can compare it to the voltage measured under load.
∆Voltage / ∆Current = resistance
12.6 - 7.6 = 5
change in current is 100 amps
5 / 100 = .05 ohms
Math makes everything simple
Starters can pull hundreds of amps for a load, so think of how low the internal impedance of the battery must be in order to deliver enough power into the starter. Or think of it this way, even small increases of internal impedance inside your car battery can cause a big voltage drop reducing power into the starter.
Lead acid battery has six 2.2v cells when fully charged. That comes out to 13.2v if you just pulled your battery off the charger, then typically each cell will settle down to about 2.1v each giving you a normal battery voltage reading of 12.6v. If it's been sitting for days then each cell can go down to 2.05v each giving you a total of 12.3v. I have seen batteries still last a while that after sitting for a while go down to only 12v, or 2v per cell. As long as the internal battery impedance is still low enough and starts the car easily it's not a problem.
What do I mean by "internal impedance"?
All batteries are a voltage source with a "source impedance" or also called "internal impedance" and "output impedance". All the same thing. If the internal impedance is .01 ohms and you draw 100 amps you will get a voltage drop inside the battery of 1v. This means if you have you volt meter on the battery posts and it reads 12.6v with no load, under the 100 amp load your meter will then read 11.6v since you lost 1v from the battery. This is why batteries get hot, that energy is dissipated internally. 100 amps and 1v is 100 watts of power the battery is producing into heat. Often times battery plates get sulfur built up on the plates, this increases the internal impedance of the battery which gives you less voltage across heavy loads like a starter. If the battery climbs up to an internal impedance of .05 ohms then with the same 100 amps of current you'll lose 5v. This will leave you with only 7.6v across your starter which isn't enough to crank the engine over.
This is why you need to measure the battery voltage before and during starting, if the voltage of the battery drops low while starting then the internal impedance of the battery is too high and you need to replace it. Reading battery voltage under quiescent (no load) conditions is practically pointless unless you can compare it to the voltage measured under load.
∆Voltage / ∆Current = resistance
12.6 - 7.6 = 5
change in current is 100 amps
5 / 100 = .05 ohms
Math makes everything simple
Starters can pull hundreds of amps for a load, so think of how low the internal impedance of the battery must be in order to deliver enough power into the starter. Or think of it this way, even small increases of internal impedance inside your car battery can cause a big voltage drop reducing power into the starter.
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There is no power to the trigger stud when the key is in the start position.
Yup, that will cause a no start and explain why replacing the starter motor didn't solve your issue.
Let's work our way backwards now.
The Aztek starter relay is in the fuse box located in the engine compartment, it should be relay #58. Remove the relay from the socket.
Ignition switch in the "off" position. Turn your meter on and set it to read continuity/resistance and clip the black lead to the battery negative and touch the red lead to pins 85 and 86 in the relay socket. The relay should have a diagram on it or markings to tell you which pins are which. One of these should have good continuity to the battery negative/ground. Say it's pin 85 that has continuity to battery negative/ground, we now want to see if power is going to pin #86 when you turn the ignition key to the "start" position. Conversely if 86 is the ground then you want to test 85 for power when the key is turned to "start". Switch your meter to read DC volts and have a friend turn the key to "start" position while probing the pin that's not ground. You should see battery voltage here when turning the key to start and nothing when returned to run.
You can check the rest of the starter circuit to see if it works simply by jumping out pins 87 and 30. One of these pins will have power to it all the time and the other pin goes to the trigger stud on the starter motor solenoid. When you jump 87 to 30 the engine should crank over.
I too have a problem. I an jump the starter from the relay and manually at the starter. I cannot get fire from the switch to the relay so i assume something is not allowing the fire from the hot wire in the switch to go to the starter wire at the switch and if so this must be a defective switch checking at the switch only. If fire is going from hot at the switch to hot at the switch to the starter pin on the switch then the only problem then is the wire from the switch to the starter relay so if that is the case is there any route the starter wire goes from the switch to the relay like another relay prior to the fuse box relay? Any help would be appreciated so i can get my daughter back to work.
Did you ever find out? Let me know as i am having a no crank, no engage to my starter also and i can jump the relay and the starter so the power is ok from the relay but i think it might be before the relay like the wire from the switch or the switch but i bought a brand new switch so i am at a loss but i guess the new switch could be bad?
I had a hellacious day trying to get my Aztec to start my battery is the right voltage but I keep on getting the clicking sound I have lights I have radio I have electric windows everything works but I just don't know where the starter is I can't find it I looked online and where they said it was under my driver side wheel I couldn't find it I have a 2004 please help and I probably know I need to replace the starter but I wanted to bang it first to see if it would work
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Yes my friend did it the voltage with a voltmeter and I don't know if I have a relay
problem . What do I tell him to look for for the Relay problem and I looked online for the image where the starter is and we couldn't find it I'm just up the creek without a paddle
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Here's a video on an Impala. Your starter is in same location.
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