No spark or Fuel

[KyleG7]

Hope someone can help. I have a 2005 Yaris automatic with no spark or fuel. The car was jump started with the leads on the wrong way. It blew the 120amp atl fuse which has now been replaced but unable to start. Everything works fine on the car just won’t start 😣. 

[Derek.w]

Have you tried disconnecting Battery then wait 5 minutes then reconnect it.

After that it down to using a meter to check that there no power to fuel pump and ignition systems.

That leaves immobiliser not working but it also worth disconnecting the alternator electrically as this may have also blown compoments.

 

[KyleG7]

14 hours ago, Derek.w said:

Have you tried disconnecting battery then wait 5 minutes then reconnect it.

After that it down to using a meter to check that there no power to fuel pump and ignition systems.

That leaves immobiliser not working but it also worth disconnecting the alternator electrically as this may have also blown compoments.

 

Thanks Derek. I will check this. I did go through all the fuses but only the ATL 120amp blew. The immobiliser does seem to work when you open the car and put the keys in the ignition the red lamp stops flashing on the radio. 

[Derek.w]

Hi Kyle,

Some 2005 cars are supplied with 3 keys one with a gray cover this one bypasses the emmobiliser.

[KyleG7]

On 9/8/2024 at 9:24 PM, Derek.w said:

Hi Kyle,

Some 2005 cars are supplied with 3 keys one with a gray cover this one bypasses the emmobiliser.

On 9/7/2024 at 10:17 PM, Derek.w said:

Have you tried disconnecting battery then wait 5 minutes then reconnect it.

After that it down to using a meter to check that there no power to fuel pump and ignition systems.

That leaves immobiliser not working but it also worth disconnecting the alternator electrically as this may have also blown compoments.

 

Thanks Derek. I will check this. I did go through all the fuses but only the ATL 120amp blew. The immobiliser does seem to work when you open the car and put the keys in the ignition the red lamp stops flashing on the radio. 

[KyleG7]

Hi Derek. No there’s no key with a grey cover but the immobiliser does seem to work. Take the key out of the ignition and the red led flashes on the car. As soon as you put the key back in it clears. I tested the  voltage at the fuel pump when you turn over the car and there’s a supply going to the pump but no voltage seems to be going to each of the coils packs. So possible fuel pump issue and maybe the alternator may have an issue also. 

[wildtapholer]

This won't help but who on earth got the leads the wrong way round when they are clearly marked, the chuckle brothers perhaps.

[Cyker]

Ack nasty, need to check all the electrics; I suspect a fuse somewhere but it's possible a module or one of the ECUs has been fried - They really don't like reversed-voltages!

 

[Mojo1010]

It could be bad news, let's hope for u it's not. As above, was told this story, someone I know fried the ECU on a lexus CT200 by either wrong way connection or were using a 24v Battery. I was told this story via a 3rd party so it was not clear. Anyway it cost £3k to fix. 

[MikeSh]

Blowing a 120A fuse takes a lot more than 120A. So I'm wondering where perhaps 200A of reverse current went. That's a lot of power (12x200=2.4kW) so something must have got fried.

[KyleG7]

Cheers guys. I’ve gone through all the fuse, only the 120amp had blown. I did get the Ecu cloned and fitted but still the same. It’s a 2005 so I believe there’s only one by the glove box. It seem the only problem I have is no ignition. So could it be the alternator ? 
Yeah it was rushing working in the dark and to make it worse I’m a spark 😞 

[Red_Corolla]

The critical sensors needed to run the engine are usually powered from a 5v supply off the ECU. Does the rev counter twitch at all while cranking? That's usually the easiest way of getting a positive sign that that side of things is working.

[KyleG7]

15 hours ago, Red_Corolla said:

The critical sensors needed to run the engine are usually powered from a 5v supply off the ECU. Does the rev counter twitch at all while cranking? That's usually the easiest way of getting a positive sign that that side of things is working.

It’s a digital display not the analog.   

[Red_Corolla]

9 hours ago, KyleG7 said:

It’s a digital display not the analog.   

That doesn't matter, unless there's no rev counter at all?

I can't guarantee the rev counter works before the engine has started, but it does on many cars. If it does, then it's a simple confirmation that the crankshaft sensor is working and the controller sees the engine turning over, which is the first thing you need in order to get the spark and injection to activate. Crank speed is only about 250rpm, so it's just a small sign of life that you'd be looking for.

[MikeSh]

On 9/17/2024 at 7:18 AM, KyleG7 said:

So could it be the alternator ? 

Unlikely. It's the Battery that does the starting. The alternator might well have been damaged and not provided power when the engine is (eventually) running, but the only way it could affect the failure to start is it it's (eg) shorting the 12V, so there isn't enough voltage to power the ignition.

What is the Battery voltage when cranking?

[flash22]

Back to Basics, does the car crank ?

Have you seen if it has any codes stored or if you can talk to the ecu - you can perform a simple flash test

If the car cranks check the voltage when cranking, has the Battery been charged or replaced

A reverse jump can blow the regulator on the alternator, remove the Aux/Fan belt

 

[KyleG7]

On 9/18/2024 at 12:13 PM, flash22 said:

Back to Basics, does the car crank ?

Have you seen if it has any codes stored or if you can talk to the ecu - you can perform a simple flash test

If the car cranks check the voltage when cranking, has the battery been charged or replaced

A reverse jump can blow the regulator on the alternator, remove the Aux/Fan belt

 

On 9/17/2024 at 7:31 AM, Red_Corolla said:

The critical sensors needed to run the engine are usually powered from a 5v supply off the ECU. Does the rev counter twitch at all while cranking? That's usually the easiest way of getting a positive sign that that side of things is working.

It’s a digital display not the analog.   

Thanks all  

when checking the Battery it measures 12v, when we crank the engine it drops to 10v. We turn the ignition on and the digital display appears when you crank the engine to see it move testing the crank sensor the display just goes off blank.  I did check on the crank sensor plug to see any voltage when cranking the engine and it reads 0v  

 

[flash22]

get a new Battery on it asap, 9-10v is enough of a drop to make the ECU do strange things, you won't be able to test a 2-wire sensor (piezoelectric) with a standard meter all you can check is the resistance

 

You can destroy a Battery with reverse polarity, they can explode in some situations

[KyleG7]

Thanks Flash. Yes I think the Battery does need replacing but when cranking the car I have my car connected from jump leads measuring  14.4 volts. Would this still give ECU issues ? Yes we did test the resistance of the sensor and the reading did adjust when moving a screwdriver in front of it if that makes sense. 

[flash22]

the old Battery can still cause an issue if connected in some cases

[KyleG7]

Fitted a new Battery today. The car cranks perfect and everything on the car works fine but still no spark. Still when turning over the car the voltage drops from 12v on the Battery to about 10v. I dropped off the belt from the alternator just in case it was dragging the voltage down when cranking but still the same. Does the alternator maintain the voltage above 12v when cranking? 

[MikeSh]

57 minutes ago, KyleG7 said:

Does the alternator maintain the voltage above 12v when cranking? 

That would be a perpetual motion machine.

[KyleG7]

21 hours ago, MikeSh said:

That would be a perpetual motion machine.

Fitted a new Battery today. The car cranks perfect and everything on the car works fine but still no spark. Still when turning over the car the voltage drops from 12v on the Battery to about 10v. I dropped off the belt from the alternator just in case it was dragging the voltage down when cranking but still the same. Does the alternator maintain the voltage above 12v when cranking? 
 

just before knocking this on the head. On a 2005 Yaris I believe there’s a fuse box in the engine bay next to the Battery and one by the drivers side under the steering wheel. Could there be any other fuse I could be missing why I’m not getting a spark. ?  Thanks all for your help 👍

[Mjolinor]

10v is normal when cracking.

[flash22]

Perform a flash test, to see if the ecu responds and read any codes, i take you have tried the spare key

Link pins 4 and 13, turn the ignition on and count the flashes