Dash lights on....need help! - Toyota Nation Forum : Toyota Car and Truck Forums

***SuperchargedMR2*** · 08-12-2011, 01:14 AM

I've been rebuilding my front brakes & suspension & something strange happened. After getting everything rebuilt I also replaced a bad battery. When I started the car up my "charge", "brake", "cooling fan" & "supercharger" lights stay on which had never happened before. I checked the fuses in the engine bay & everything looked okay.

Any ideas about where to look? Thanks for the help.

***MR2Jedi*** · 08-12-2011, 09:18 AM

Only thing I can think of is to disconnect battery and pull ECU fuse for a minute.
Then reinstall ECU fuse and connect battery and see if it clears it.

***SuperchargedMR2*** · 08-13-2011, 12:24 AM

Quote:

Originally Posted by MR2Jedi

Only thing I can think of is to disconnect battery and pull ECU fuse for a minute.
Then reinstall ECU fuse and connect battery and see if it clears it.

I'll try that & see what happens. I did disconnect the battery to see if that helped but it made no difference. I was wondering if it could be a fusible link too but I need to find out where they are located to test them.

Any other ideas from anyone?

***SuperchargedMR2*** · 08-14-2011, 09:34 PM

I checked several things & I think it's either the alternator or external VR. I may drive it down to a local shop & see if their equipment can help tell me for sure.

toyotaspeed90 · 08-16-2011, 10:08 AM

The ecu has no impact on those lights. They are actually wired in to the alternator (which is, then, wired to the ECU...)

somehow installing a new battery made your alternator angry at you.... what sort of battery did you get?

Tech1984 · 08-16-2011, 01:18 PM

You may be on to something with the fusible link. See if there's a positive battery connection that may have fallen behind the battery when installing.
I'm leaning towards fusible link problem.

toyotaspeed90 · 08-17-2011, 12:25 PM

no.

at least in stock form the AW11's main wiring harness is horrible (I don't care who disagrees with me... it is). There's 2 main cables that come off of the harness... 1 for the starter and 1 for everything else in the car (all accessories power, engine power, and alternator charging).... there's 1 fusible link that runs on this wire that's about 5" long or so... then from there it gauges up to a 6 ga cable.... 10" further down or so 2 more 6 ga cables split off of it to run to the cab. The main cable runs to the alternator... within 10" or so of it one of the 3 wires from the alt plug splits off of this main 6ga cable as well.

It's a horrible design that lends itself to really bad corrosion.....

Now the really bad news..... if yours is corodded.... this runs through the main EFI harness.... in order to replace it requires pulling the entire harness apart between the alternator and the battery (and the 2 grey connectors on the drivers-side strut tower).

Before I did the Mk1.22 I rebuilt most of the engine harness because of this issue... here are just a couple snap shots.... my fix (when it was still in the car) before rebuilding the harness was to cut the end off the alt connection, leave it connected to the battery, then run a new 6ga cable straight from the battery to the alternator.

***SuperchargedMR2*** · 08-17-2011, 06:52 PM

Quote:

Originally Posted by toyotaspeed90

no.

at least in stock form the AW11's main wiring harness is horrible (I don't care who disagrees with me... it is). There's 2 main cables that come off of the harness... 1 for the starter and 1 for everything else in the car (all accessories power, engine power, and alternator charging).... there's 1 fusible link that runs on this wire that's about 5" long or so... then from there it gauges up to a 6 ga cable.... 10" further down or so 2 more 6 ga cables split off of it to run to the cab. The main cable runs to the alternator... within 10" or so of it one of the 3 wires from the alt plug splits off of this main 6ga cable as well.

It's a horrible design that lends itself to really bad corrosion.....

Now the really bad news..... if yours is corodded.... this runs through the main EFI harness.... in order to replace it requires pulling the entire harness apart between the alternator and the battery (and the 2 grey connectors on the drivers-side strut tower).

Before I did the Mk1.22 I rebuilt most of the engine harness because of this issue... here are just a couple snap shots.... my fix (when it was still in the car) before rebuilding the harness was to cut the end off the alt connection, leave it connected to the battery, then run a new 6ga cable straight from the battery to the alternator.

I'm keeping my fingers crossed that this is not the issue. The car is kept indoors, always has been even from the previous owner. It doesn't even get driven in bad weather anymore but one never knows.