Toyota Repair Problems? Ask a Mechanic for Answers ASAP
Hello. Welcome to Just Answer. Please allow me to assist you. Please check the following fuses:
30 amp AM2
30 amp ST3
Sorry about that; the site crashed. Do you still need assistance your starter problem?
Hello. Sorry about the delay, something happened to the site.
What type cab do you have? Standard, access, dual? Wiring is slightly different
Thanks. When you make the starter run, how are you doing it?
How many miles on the truck, please?
And, please tell me is this is an automatic, or manual transmission
Ok. We need to do a couple voltage checks. Do you have a 12 volt DC testlight?
Ok. We need to verify that we have power in the park/neutral switch on the side of the transmission. Please check the following wires with the key turned to start (you are going to have somebody to help you)
On the park/neutral switch, on the side of the transmission, there is a wire connector. In the connector there are several wires
We need to see if there is power coming to the P/N switch, with the key in the Start position in the following two wires:
Power in is Blue, with a Red tracer
Power out is a solid Pink wire.
If you have power at the Blue with a red tracer, and no power in the Pink wire, the P/N switch is bad. There have been observations on the wires in the connector being corroded also..
Also: I neglected to mention one more fuse. Please check the 5 amp STA fuse. Apologies for that omission.
The 5 amp STA fuse in on the fuse panel under the dash, on the driver side.
Power must flow to the center wiper that allows power to go to the P or N contacts to fulfill the circuit.
If the center wiper is not touching either contact, the circuit will remain open; no power is sent to energize the relay coil
Did you check the 5 amp STA fuse?
The 5 amp STA fuse powers the Blue with a red tracer
Please verify that you have 12 VDC at both sides of the STA fuse.
Check voltages withthe key in the Start position please.
There will not be voltage present in the Blue/red wire if the Ign switch is not turned to start
When you get time, please remove the starter relay, and check for voltage in the individual cavities.
The 5 amp STA fuse is good? OK. Does the 5 amp STA fuse have power running thru it? If not, remove the lower panel under the dash, and look for the ignition switch wiring connector. Find the Black with a White tracer wire, and check it for battery voltage in the Start position.
Sorry about the delay, my wireless modem quit on me.
OK, let me describe the power flow so we can get a better grasp on the diagnosis
Power comes form the battery, thru 2 fuses
30 amp AM2 and 30 amp ST3
AM2 goes to the ignition switch
When the key is turned to start, power flows from the ignition into a Black with a white tracer
The Black with a white tracer powers up the 5 amp fuse STA
The STA fuse protects the ECM, where power flows thru the STA fuse into the ECM
Out of the ECM, this is where the blue with a red tracer feeds the P/N switch
If you have power in the STA fuse, both sides, and no power in the Blue witha red trace at the P/N switch on the side of the transmission, you either have an open circuit between the ECM and the P/N switch, or, an issue with the ECM (which is rare).
At this point, we need to find out why there is no power in the Blue with a Red trace on the P/N switch.
you could remove the ECM and ohm-test the blue/red trace wire between the two locations.
If we are not getting power to the Pink wire on the output side of the P/N switch, which is supposed to transfer power form the Blue/red wire, we are not powering up the starter relay.
According to the wiring diagram I am looking at, that sounds feasible.
Was the key turned on?
Then we are back to a wiring issue. If it turns over, and does not start, the ECM is looking for (and possibly not seeing) a start signal from the key switch. The 5 amps STA fuse goes form the fuse panel across the dash, to a 26 pin connector above the ECM. The wire is Red with a blue tracer, pin 15 (starting at the top, and counting across. There are a few different size terminals in this connector.). We need to find out if the wire form the connector is good to the ECM. This diagnosis will involve removing the glove box, and the ECM from its mounting.
Worth a shot. I did not know you cut that wire.
Yes. You need to back trace the red with a blue tracer
If the vehicle has a security system, the black box (if it is what I think it is) will not allow the vehicle to start, if the security box/computer is bad.
The pink wire from the P/N switch goes to the security box
out of the security box, the wire becomes green with a red tracer, which powers the coil side of the starter relay
Between the 5 amp STA fuse, to the ECM, the wire is Red with a blue tracer. Out of the ECM is the Blue with a Red tracer, and that is the wire that goes to the P/N switch.
ECU=Electronic Control Unit
ECM= Electronic Control Module
Both are one and the same. Sometimes referred to as the "fuel injection computer".
On the newer vehicles, the immobilizer system interacts with the ECM/ECU, and custs power to the fuel pump, if the wrong key is inserted into the engine. This is an anti-theft feature, which is supposed to disable the vehicle's starting ability, if someone attempts to "hot-wire" the ignition.
Sorry. We are under very strict rules when it comes to personal contact off site; your e-mailing me is prohibited. This rule is in place to protect your identity. I cannot bend the rules on this. I apologize for that, and I hope you understand
You can e-mail [email protected], or [email protected] attach the picture, and request they forward them to me.. The good people there have the ability to forward the pictures to me, if that is acceptable to you
No. The picture has not been transmitted as of yet. Sometimes, they have a heavy influx of e-mail. I am sure that it will be coming shortly. When I see it, I will respond.
OK I see the picture.
I believe that the device that you are showing me is the "Transponder Key Amplifier" unit. If it is bad, the engine will crank, but no fuel will be allowed into the cylinders; this is part of the anti-theft system
It is sounding more and more like you need the transponder part of the ECU interface checked.
This needs to be done by a Toyota technician with the Toyota scan tool.
Sorry. No. It is impossible to bypass. I wish there was, but, there is not. Apologies.