Toyota Corolla 2003 80,000 miles no crank no start, battery and starter both test ok

Maintenance/Repairs
41

Bill - using the voltmeter connected to battery -ve and metal case of the starter, the reading is zero. For some reason this time I couldn’t get the car to catch, although everything turned over, when directly connecting the starter to the positive battery terminal.

I also looked at the battery - it measures 12.24 volts without doing anything, and drops to 11.6 when cranking. Is this too low? I did try a new battery yesterday, which did not start the car, but maybe the older battery is contributing?

42

11.6 when cranking is fine.

But if you are cranking now, the problem is different. You originally said it would not crank, which indicates an electrical problem. If you crank but it doesn’t start, you have to look at spark, fuel, etc.

43

Sorry, cranking the key. Engine still does not crank.

Also, I retested the smaller solenoid wire (pierced the wire and other end of voltmeter on +ve battery) - its now reading 12v when the key is out, or when the key is turned. I have no idea why this changed

44

What in the world does “cranking the key” mean?

You need to get this to a good mechanic.

45

Cranking the key, i.e. holding it in the position it would crank the engine.

46

When you take voltage readings the results you get depends on how you placed the meter probes. The black (COM) wire probe of the meter is usually placed on a good ground point and voltage readings are referenced to that, ground, which is tied to the negative battery post.

It appears your problem is power is not getting to the solenoid coil for some reason to turn it on when the ignition switch is in the START mode. From previous testing it seems power is getting to the clutch safety switch but not sure if it is getting beyond that point. Either the switch is bad or there is a break in the wire after the safety switch. This isn’t a complicated problem. You have also proved that when the solenoid does have power getting to it the starter works like it should.

47

My car is a Corolla too, but earlier model, early 90’s. On mine the starter motor only has two places to connect wires to. One gets a big thick wire that comes directly from the battery +. That one has a bolt & nut connection. That’s the battery positive input to the starter motor. It always measure battery voltage, whether the engine is cranking or not even turned on. During cranking the voltage is less b/c the battery voltage is less. Like you say, a good battery measures around 11-11.5 volts during cranking. The other is a push-in connection with a small wire. That’s the “start” input to the starter motor. Both must measure at least 10.5 volts between the respective terminal and the starter case during attempting cranking.

There’s a third connection to the starter motor for ground, but that isn’t done using a wire. It is done by bolting the starter motor case to the engine. The starter motor case is connected to the starter motor ground internally. Likewise the engine is connected to the battery ground with a wire. That’s the reason you test the voltage between the terminal and the starter case in the tests above. From your posts above, I don’t see that you’ve actually done either of those two tests yet.

When you measure voltage, you always measure between two points in the circuit. The + input to the volt meter touches one point, and the - input to the meter touches the other. So for the first test above the + input to the meter would touch the bolt&nut connection (the + battery input) and the - input to the meter would touch the starter motor case.

From what I can infer, your problem appears to be the “start” input to the starter motor is much too low, 0.9 volts. It should measure as stated above, 10.5 volts (measuring terminal to case) or above during attempted cranking (key in start).

For what it’s worth, I’ve had this same problem on my own Corolla. When tested, mine measured about 3.5 volts. I can’t speak to your model-year, you’d have to find a wiring schematic for your car, but on mine the circuit starts at the battery, goes through a fuse, then through the ignition switch, then through a small under-dash “starter” relay controlled by the clutch safety switch, then to the starter motor “start” terminal via the small wire. I found the problem to be in the ignition switch and the clutch safety switch. Both had too high of resistance. There’s a lot of current in the “start” circuit too, around 15-20 amps, so the resistances along the entire circuit path have to be very low.

What I did to fix it was to bypass the clutch safety switch to verify that was the problem, and install another relay into the circuit so the ignition switch didn’t have to handle so much current. I could have alternately just replaced the ignition switch. In any event, with those fixes, the “start” terminal now measures about 11 volts during attempted cranking. And it cranks fine.

If you are only measuring 0.9 volts at the “start” terminal during attempted cranking, it’s usually of no use spending time replacing starter motors. The problem is most often the circuit before the starter motor. There’s a small possibility the starter motor coil is shorted out and this would cause the same symptom. There’s a spec for the coil resistance so that’s how to disprove that possibility, which doesn’t require remove the starter motor. Best of luck.

48

Thanks for all your help guys. I’m at work today, will hopefully get chance to look again tonight or tomorrow.

I will try bypassing the clutch safety switch, and measure the input voltage at the solenoid - if that is then normal (whereas it was 0.9) then I would assume the clutch safety switch is bad. However, I would also expect the car to start previously when I bypassed this switch.

The click I hear sounds like a relay, and comes from the glovebox. I cannot see or feel a relay in there, but is it possible there is a short in there, causing that noise?

49

The sound coming from the glove box area may be a relay but it most likely is for something else, not the starter circuit. You need 12 volts to get to the starter solenoid lead in order for it to turn on and switch power to the starter motor.

50

Ok, so I looked into the click under the glove box. Found a relay, which I switched out. No change, new one still clicks, and the clicking relay was good.

I also tested the ignition switch wires, all seem to be working ok - ie 2 are always hot, 1 or 2 are hot only when key is an ‘Acc’, two are only hot when key is turned to start.

I’m going to try and get my head around finding a bad ground, it’s all that’s left?

51

I think you replaced the HVAC blower relay.

A few days ago you indicated that there is no power to the starter solenoid, the next step is to check the inputs and outputs of the starter relay located in the left interior junction block/fuse block. The results will lead to the next step.

52

Hi Nevada,

The starter solenoid ignition wire shows 0volts when not turning the key, 0.9 volts when turning to try and start the engine

The large positive clip is constantly at 12v

There is no evidence of a ground issue, as previously described, and grounding the starter directly to the -ve battery terminal does not help.

I checked all the visible fuses in the left side of the engine block, none are blown, There are some more fuses that are pretty inaccessible to the left of the steering wheel. This is where I managed to remove and test the starter relay, which was working fine when I tested with a 9v battery. I can also feel this relay click when turning the key, so I believe power is getting past - ignition switch, starter relay, clutch safety switch. It seems to be lost somewhere between that and the starter solenoid.

53

If your vehicle has the anti-theft option then there is an extra cut relay circuit involved between the clutch switch and the starter relay which is controlled by the ECU. The ECU makes a ground connection on the blk/red wire going to the coil of the relay. Power to the relay coil is supplied by the clutch switch. To bypass that relay connect the blk wire to the blk/wht wire going to the relay.

54

Hi Cougar,

Thanks, I don’t think there is an antitheft option on it. I can just about access the starter relay to remove it if I stick my head up in the footwell, but have no access to the wiring short of removing the whole dash. Which I will do if you think it is possible?

55

I wouldn’t do that. If the option isn’t there then there should be a blk wire between the clutch switch going to the coil of the starter relay in the instrument panel to turn on the relay. If you have voltage on that wire while trying to start the engine and the relay doesn’t work then you need to check the ground connection to the relay coil. It is a wht/blk wire. It should have no voltage on it when trying to start if the connection to ground is good. If those things are good and the relay is working then switched power through the relay contacts isn’t getting to the starter solenoid for some reason. My info shows the wire color is blk going to the solenoid.

56

If you have 12 volts at the “start” output of the ignition switch, and 0.9 volts at the “start” input to the starter motor, then you know the problem and it is just matter of tracing the circuit point to point from the ignition switch to the starter motor until you find where it changes from 12 volts to 0.9 volts. Be sure to do this during attempted cranking. Resistance problems only show up with current flow.

57

Finally fixed this! I took it to a shop, and they were usually getting 0.9v at the solenoid, but 12v for the first half a second the key was turned. We changed out the relay, and it is now fine. I don’t really understand how the relay could test fine, but still be the problem, but hey ho. The mechanic said it couldn’t kick out the right amps. Just thought I’d let you know, in case anyone sees a similar problem. Thanks again for all your help, most grateful

58

Congratulation on getting to the bottom of it. I know from personal experience it’s very frustrating when you car won’t crank reliably.

Was it the starter solenoid relay you changed out? Or the under-dash relay? Corolla’s seem to have a reputation for the starter solenoid relay contacts getting burned and becoming intermittent no-cranks.

59

Hi George,
It was the under dash relay. Thanks again, Andrew

60

This happened to me with my van. It ended up being the fuel pump. It would usually start cold but not always. Went on for 3 weeks before I could get it diagnosed because it’s not a common problem for the fuel pump to cause. Sounds like the exact same situation.