No check engine light
#1
03-09-2014, 04:01 AM
ACTIVE: Camry woes (Solved 1/2)
Hi guys! Issue two still not solved. Replaced loom plug and ran a new wire to the fuse, still the same issue. Seems to be heat related.
(Solved, please scroll to comment #4 to skip this problem and solution, keep reading if you want to learn things.
)
I did a quick search and nothing close enough came up.
So my gf has a 98 Camry CSI, 5SFE four pot. It underwent an inspection, and had a number of things repaired, in this instance the alternator was replaced due to the battery light coming on when the engine warmed. Replacing that, the battery light was still an issue, as it turns out we awoke this morning to a completely dead car. No battery whatsoever. I stole the battery from my Astra and got her down to the show to replace it. He checked the old battery (dead), my battery from the Astra (excellent) and the new one with the alternator and everything checks out.
Yet the light persisted. We drove home with intentions to book it in to a sparky for a diagnosis, and now the car won't fire. Normally the following lights come on at ignition:
Battery
Oil pressure
Seat belt (for a few seconds)
Door open (where applicable)
Park brake (if on)
Check engine (until the engine is started due to a no reading on the CAS)
This was considered normal illumination as once started the lights went out and all went well.
Until now.
DUN DUN DUUNNNN!!
The check engine light now doesn't come on at all at IGN and there is no firing. Our fob was out of action for ages too, but with some surgery I have got it to lock and unlock the car. We tried "master" and "sub" keys, numerous methods to reset the anti-theft system, all to no avail.
The next theory was that the ECU is suddenly not getting any power (a key point I recall from when I overlooked a missing/blown fuse in a TR Magna I rebuilt a couple of years back) but all the fuses check out and the main relay is clicking when inserting with the IGN on. So I assume the ECU is getting power at least to there.
Now the alarm has gone of a couple of times, both reset with the key and then with the fob.
Would I be right in assuming the immobilizer is still active, effectively killing the ECU power and preventing the use of the car?
What's the solution?
Mike - Breaking cars since 1998.
(Solved, please scroll to comment #4 to skip this problem and solution, keep reading if you want to learn things.
)I did a quick search and nothing close enough came up.
So my gf has a 98 Camry CSI, 5SFE four pot. It underwent an inspection, and had a number of things repaired, in this instance the alternator was replaced due to the battery light coming on when the engine warmed. Replacing that, the battery light was still an issue, as it turns out we awoke this morning to a completely dead car. No battery whatsoever. I stole the battery from my Astra and got her down to the show to replace it. He checked the old battery (dead), my battery from the Astra (excellent) and the new one with the alternator and everything checks out.
Yet the light persisted. We drove home with intentions to book it in to a sparky for a diagnosis, and now the car won't fire. Normally the following lights come on at ignition:
Battery
Oil pressure
Seat belt (for a few seconds)
Door open (where applicable)
Park brake (if on)
Check engine (until the engine is started due to a no reading on the CAS)
This was considered normal illumination as once started the lights went out and all went well.
Until now.
DUN DUN DUUNNNN!!
The check engine light now doesn't come on at all at IGN and there is no firing. Our fob was out of action for ages too, but with some surgery I have got it to lock and unlock the car. We tried "master" and "sub" keys, numerous methods to reset the anti-theft system, all to no avail.
The next theory was that the ECU is suddenly not getting any power (a key point I recall from when I overlooked a missing/blown fuse in a TR Magna I rebuilt a couple of years back) but all the fuses check out and the main relay is clicking when inserting with the IGN on. So I assume the ECU is getting power at least to there.
Now the alarm has gone of a couple of times, both reset with the key and then with the fob.
Would I be right in assuming the immobilizer is still active, effectively killing the ECU power and preventing the use of the car?
What's the solution?
Mike - Breaking cars since 1998.
Last edited by Mike Draper; 09-12-2014 at 06:15 PM. Reason: Multiple issues, thread renamed
#2
03-09-2014, 07:01 AM
Nevermind people. Here's what it was.
Fuse.
EFI.
No. Kidding. (Censorship edit)
15A EFI fuse is one of the three lines that feeds the ECU. Makes sense when I think about it. If the EFI is blowing fuses due to malfunction, the ECU won't fire up.
Keep that in mind people!
Mike
Fuse.
EFI.
No. Kidding. (Censorship edit)
15A EFI fuse is one of the three lines that feeds the ECU. Makes sense when I think about it. If the EFI is blowing fuses due to malfunction, the ECU won't fire up.
Keep that in mind people!
Mike
#4
03-10-2014, 12:43 AM
I do have another issue though... related. The charge light comes on once the car is warm, despite everything working within specification.
I've contacted the supplier of the alternator and am awaiting their response.
Mike
I've contacted the supplier of the alternator and am awaiting their response.
Mike
#5
03-11-2014, 12:37 AM
Attached is the wiring for the Toyota Sienna (I couldn't find the exact circuit to suit the Camry, but I understand it is the same car). Only I only have the HT cable and the two pin sensor from the regulator. If the AM2 fuse is damaged, could it work until it gets hot, then trigger the light to come on?
https://www.dropbox.com/s/umgursgzdjdphw4/014cs.pdf
Thoughts?
Mike
https://www.dropbox.com/s/umgursgzdjdphw4/014cs.pdf
Thoughts?
Mike
Last edited by Mike Draper; 03-11-2014 at 12:40 AM. Reason: Forgot to link... :D
#6
03-11-2014, 06:33 AM
Grrr!
It has me stumped! I tested the two possible theories left aside from a faulty regulator (on a new alt)...
1- Changing the battery and alternator meant possibly loose connections, or;
2- Bad fuses on the AM2 and ALT-S line.
Cleaned all the terminals, tightened them until I could near snap the socket drive, and started the engine. While cold, the light is out. Unplug the sensor and the alternator stops charging. Which goes against the wiring...
Plug it back in and boom it kicks in and the light goes out, until it gets hot. Then it comes back on despite charging.
Now I'm on a learning path here. I knew what they did but not how. So after some intensive research I've picked up this:
Obviously the main cable goes to the + side of the battery to deliver a charge. This of course relies on the mounted alternator being earthed properly. I don't believe that is my issue. It's tighter than a nun's...
It's definitely spinning, so belt tension is ok...
The two wires remaining are the sensors. One is a yellow one which drives the light, and in this case it's active. The white one goes directly through a fuse to the battery. I believe the regulator checks the current on this line against the main line and if it is out of range the light is triggered. What would cause an otherwise clean and untouched system to report a possibly out of range voltage/current, other than a bad alternator?
I can say it is DEFINITELY charging. It would not have taken us a good 300km round trip on just the battery, with radio, amp, air-con, low beam lighting (rain...). I don't care who tells me otherwise.
It otherwise never misses a beat now. But now I have a faulty reporting system that can not accurately tell me if the alternator or battery IS failing, until it is too late...
Any ideas? o.O
It has me stumped! I tested the two possible theories left aside from a faulty regulator (on a new alt)...
1- Changing the battery and alternator meant possibly loose connections, or;
2- Bad fuses on the AM2 and ALT-S line.
Cleaned all the terminals, tightened them until I could near snap the socket drive, and started the engine. While cold, the light is out. Unplug the sensor and the alternator stops charging. Which goes against the wiring...
Plug it back in and boom it kicks in and the light goes out, until it gets hot. Then it comes back on despite charging.
Now I'm on a learning path here. I knew what they did but not how. So after some intensive research I've picked up this:
Obviously the main cable goes to the + side of the battery to deliver a charge. This of course relies on the mounted alternator being earthed properly. I don't believe that is my issue.
It's tighter than a nun's...It's definitely spinning, so belt tension is ok...
The two wires remaining are the sensors. One is a yellow one which drives the light, and in this case it's active. The white one goes directly through a fuse to the battery. I believe the regulator checks the current on this line against the main line and if it is out of range the light is triggered. What would cause an otherwise clean and untouched system to report a possibly out of range voltage/current, other than a bad alternator?
I can say it is DEFINITELY charging. It would not have taken us a good 300km round trip on just the battery, with radio, amp, air-con, low beam lighting (rain...). I don't care who tells me otherwise.
It otherwise never misses a beat now. But now I have a faulty reporting system that can not accurately tell me if the alternator or battery IS failing, until it is too late...Any ideas? o.O
#7
03-11-2014, 09:42 PM
White wire = Alt-B fuse
Yellow=Alt charge light on dash
Red/Blue=Gauge fuse
Black/Green=100A fuse. If this fuse is bad the car may run but will have no brake, tail, dash lights, power windows and doors, not shifter unlock and more. There was a recent post on at this site on what happens when this fuse is blown.
Case is ground
Rather then keep tightening alt mount bolt clean contact surfaces of mount and alt or run wire from alt case to chassis. Make sure the electrical jumper between engine and chassis is good.
AM2 fuse powers among other things injectors and fuel pump relay. If blown, engine would not run.
AM2 and Alt-S receive power from same connection in fuse box.
Check voltage between white wire connection at alt and ground. Should be 13.9-15.1v at 2000 rpm, temp 77F (engine cold). Then 13.5-14.3v at 5000 rpm, temp at 239F (engine hot).
Yellow wire contact and ground should be 0-4v ign switch on, engine not running.
If you have an amp AND a volt meter can run a few more tests.
Yellow=Alt charge light on dash
Red/Blue=Gauge fuse
Black/Green=100A fuse. If this fuse is bad the car may run but will have no brake, tail, dash lights, power windows and doors, not shifter unlock and more. There was a recent post on at this site on what happens when this fuse is blown.
Case is ground
Rather then keep tightening alt mount bolt clean contact surfaces of mount and alt or run wire from alt case to chassis. Make sure the electrical jumper between engine and chassis is good.
AM2 fuse powers among other things injectors and fuel pump relay. If blown, engine would not run.
AM2 and Alt-S receive power from same connection in fuse box.
Check voltage between white wire connection at alt and ground. Should be 13.9-15.1v at 2000 rpm, temp 77F (engine cold). Then 13.5-14.3v at 5000 rpm, temp at 239F (engine hot).
Yellow wire contact and ground should be 0-4v ign switch on, engine not running.
If you have an amp AND a volt meter can run a few more tests.
#8
03-12-2014, 03:53 AM
So I bought a cheap multimeter today. We also just drove 200km with the system under load and the lights on. No issues. Except. That. Light.
So with some testing advised above, yellow light cable engine off shows zero. Odd, given it was powered. White cable showed 14.4, same as the hot line when idling. Idling under load it showed 12.2v but at 2k it rose to 14ish again. The whole time we tested the alt light did not come on at all.
Then we closed the bonnet. Given it only did that upon bumping it, I assume a loose or damaged loom at the alternator.
Looks like I'm sourcing a replacement loom section, as I don't know which part of the entire white cable is broken.
Stay tuned!
Mike.
So with some testing advised above, yellow light cable engine off shows zero. Odd, given it was powered. White cable showed 14.4, same as the hot line when idling. Idling under load it showed 12.2v but at 2k it rose to 14ish again. The whole time we tested the alt light did not come on at all.
Then we closed the bonnet. Given it only did that upon bumping it, I assume a loose or damaged loom at the alternator.
Looks like I'm sourcing a replacement loom section, as I don't know which part of the entire white cable is broken.
Stay tuned!
Mike.
#9
03-13-2014, 10:05 AM
The alt light works as follows:
One circuit of the light is connected to the IGN fuse, the other end to the alt regulator yellow wire. When the ign key is on and engine is not running. The electrical connection at the alt is grounded. This completes the light circuit and turns on the light.
If the engine is running, the voltage at the alt regulator yellow wire should be the same as the IGN fuse. Since there is no electrical potential across the light, it remains off.
If there is an increase in voltage on one side of the light or the other, the light can come on. As in the voltage at the ALT yellow wire is higher or lower the IGN fuse wire.
If possible compare voltage at alt yellow with IGN fuse voltage when light come on.
The IGN fuse connects to the IGN switch (AM 2 side), then AM2 fuse to the battery side of the 100A alt fuse, then through the battery cable fusible link to battery.
White Alt wire goes to ALT-B fuse, then the battery side of the AM2 fuse, then same as above.
Red/Blue wire to IGN switch (AM 1 side), then AM 1 fuse, 100A alt fuse, then same as above.
Black/Green wire goes to 100A Alt fuse, then same as above.
Or suppose could be internal alt issue. If a rebuilt alt it is possible to have problems out of the box. Rebuilt quality can vary greatly!
One circuit of the light is connected to the IGN fuse, the other end to the alt regulator yellow wire. When the ign key is on and engine is not running. The electrical connection at the alt is grounded. This completes the light circuit and turns on the light.
If the engine is running, the voltage at the alt regulator yellow wire should be the same as the IGN fuse. Since there is no electrical potential across the light, it remains off.
If there is an increase in voltage on one side of the light or the other, the light can come on. As in the voltage at the ALT yellow wire is higher or lower the IGN fuse wire.
If possible compare voltage at alt yellow with IGN fuse voltage when light come on.
The IGN fuse connects to the IGN switch (AM 2 side), then AM2 fuse to the battery side of the 100A alt fuse, then through the battery cable fusible link to battery.
White Alt wire goes to ALT-B fuse, then the battery side of the AM2 fuse, then same as above.
Red/Blue wire to IGN switch (AM 1 side), then AM 1 fuse, 100A alt fuse, then same as above.
Black/Green wire goes to 100A Alt fuse, then same as above.
Or suppose could be internal alt issue. If a rebuilt alt it is possible to have problems out of the box. Rebuilt quality can vary greatly!
#10
03-14-2014, 03:25 AM
It's a broken / worn wire. With the heat it is expanding and breaking the circuit, and the alt is reporting a problem. Nothing to stress about. False positive.