8th Gen Gauges

quote name='fishexpo101' post='143949' date='Apr 17 2007, 09:11 AM']Changing the sensor may not do anything for you in this case - the thermistor is usually hooked into a bridge or a voltage divider circuit composed of high precision and stability resistors - the resulting voltage drop across the thermistor is feed into the ECM and pumped to the display. You may be able to get Toyota to change the display in the ECM or be easiest to grab a LCD display with C on it. Some cars can have the user change the metric used for temperature, but I don't remember off-hand if the Corolla did as well - it would be in the Owner's manual if it had that capability.

Thanks for the reply. There is no way for the owner to 'toggle' the units they way yuo can in some of todays cars, pontiacs for example.

I am curious about changing it in the ECM. I wonder is it a wholesale metric vs imperial setting that refers to speedometer and everything else, or if the outside temp. can be changed over to metric manually.

it would be interresting to see whether or not swapping the display would work. Unfortuantely, it is rare to find a '00 scrapped to recover the cluster, and if I did find one it would be very expensive.

I did find this one on ebay:

Canadian Cluster from '98 Corolla

I wonder whether or not the signal from the ECM is processed at the display, or if the LCD simply displays the output from the ECM.

Again, the local dealership really has no idea on how to accomplish this task. Thats why I am full of questions. I am starting to doubt whether or not it can even be done.

Changing the sensor may not do anything for you in this case - the thermistor is usually hooked into a bridge or a voltage divider circuit composed of high precision and stability resistors - the resulting voltage drop across the thermistor is feed into the ECM and pumped to the display. You may be able to get Toyota to change the display in the ECM or be easiest to grab a LCD display with C on it. Some cars can have the user change the metric used for temperature, but I don't remember off-hand if the Corolla did as well - it would be in the Owner's manual if it had that capability.

Thanks for the reply. There is no way for the owner to 'toggle' the units they way yuo can in some of todays cars, pontiacs for example.

I am curious about changing it in the ECM. I wonder is it a wholesale metric vs imperial setting that refers to speedometer and everything else, or if the outside temp. can be changed over to metric manually.

it would be interresting to see whether or not swapping the display would work. Unfortuantely, it is rare to find a '00 scrapped to recover the cluster, and if I did find one it would be very expensive.

I did find this one on ebay:

Canadian Cluster from '98 Corolla

I wonder whether or not the signal from the ECM is processed at the display, or if the LCD simply displays the output from the ECM.

Again, the local dealership really has no idea on how to accomplish this task. Thats why I am full of questions. I am starting to doubt whether or not it can even be done.

Yes, that would be what is needed to add a tach and outside temp to gen 8 USDM Corollas.

I might have posted this before, but I found two common EEPROM chips in the cluster, one under speedo and one under tach. I wonder if these two chips hold the keys to switching outside temp from C to F (and vice versa, I prefer seeing C), "editing" odo readings, and calibrating the speedo to the exact wheel size we use after we go +1 or more. You know, there's enough clearance to add a DIP8 socket there.

After some more discussion at this newer thread reminded me to look at the gauge cluster wiring once again because another fellow member without a tach scored a 01 cluster with tach and ran into problems again, here are some additional information, including an action plan to get around that issue.

The connectiors are named, starting from the the side with your cruise and door ajar lights among others, as follows, per my 1999 factory diagram:

C11 (it's brown)

C12 (white)

C13 (blue)

C14 (gray)

Pin 6 of C11 has a wired spot available for a lamp that lights up when ignition is ON, and this pin goes to ground. An additional spot below that isn't wired, but once wired, would also light up with under the same condition. Be creative! However the faceplate is black over the area for these two spots. I am still finding out how to put my own icon there.

Pin 9 of C12 is where the factory theft deterrent system indicator LED is wired to. I wanted to find a cluster with tach AND provision to add a module there.

baadpuppy's 3-pin connector "C2" is actually for a bulb check relay, and is the same throughout 98-02.

Now we come to connector C13 and the fun begins.

For 1998-2000 clusters, Pin 1 is high beam, pin 2 is left turn signal, pin 3 is defroster, pin 9 is "4P" signal from your speedo that sends vehicle speed pulse to the engine computer, pin 13 is for right turn signal. The other legs of all these lamps are tied together with pin 12, which is ground.

For 2001-2002 clusters, pin 1 is high beam, pin 2 is return leg of high beam lamp, pin 3 is left turn signal, pin 9 is still 4P, pin 13 is still right turn signal, pin 12 I think is still ground. Only L & R turn lamps are tied together to pin 12; spot for defroster lamp is no longer wired. Thanks Jim for the pics.

If you are installing a 01 cluster, your first priority is to fix the turn signals. For that, you need to vacate pin 3 (your defroster indicator) and move it to pin 5 or 8 which is unused. Then move pin 2 to pin 3. After completing the move, you get turn signal back, but lost high beam and defroster lamp. But won't be for long.

Now you need to rebuild the defroster connection. Look at Jim's pictures and you'll see a solder blob for one end of a jumper wire. This is the ground point we're tapping into. First scrape off some oxidation from both contact points, then stick a lamp holder into the spot so you don't solder too much and prevent you from actually installing a bulb there. Now take a small wire, solder one end to the blob, and the other end to the lower pad. Scrape off the coating off the tip of copper finger of either pin 5 or 8 of C13 above, depending on where the defroster wire is moved to, then solder another wire there. Tack the other end to the defroster spot and you gain it back!

For high beam, solder a wire to the pad similarly to the pad that goes to pin 2, and wire it to ground using the blob above. Now you can put everything back together and everything should work normal. Noticed how I never mentioned cutting traces?

After some more discussion at this newer thread reminded me to look at the gauge cluster wiring once again because another fellow member without a tach scored a 01 cluster with tach and ran into problems again, here are some additional information, including an action plan to get around that issue.

The connectiors are named, starting from the the side with your cruise and door ajar lights among others, as follows, per my 1999 factory diagram:

C11 (it's brown)

C12 (white)

C13 (blue)

C14 (gray)

Pin 6 of C11 has a wired spot available for a lamp that lights up when ignition is ON, and this pin goes to ground. An additional spot below that isn't wired, but once wired, would also light up with under the same condition. Be creative! However the faceplate is black over the area for these two spots. I am still finding out how to put my own icon there.

Pin 9 of C12 is where the factory theft deterrent system indicator LED is wired to. I wanted to find a cluster with tach AND provision to add a module there.

baadpuppy's 3-pin connector "C2" is actually for a bulb check relay, and is the same throughout 98-02.

Now we come to connector C13 and the fun begins.

For 1998-2000 clusters, Pin 1 is high beam, pin 2 is left turn signal, pin 3 is defroster, pin 9 is "4P" signal from your speedo that sends vehicle speed pulse to the engine computer, pin 13 is for right turn signal. The other legs of all these lamps are tied together with pin 12, which is ground.

For 2001-2002 clusters, pin 1 is high beam, pin 2 is return leg of high beam lamp, pin 3 is left turn signal, pin 9 is still 4P, pin 13 is still right turn signal, pin 12 I think is still ground. Only L & R turn lamps are tied together to pin 12; spot for defroster lamp is no longer wired. Thanks Jim for the pics.

If you are installing a 01 cluster, your first priority is to fix the turn signals. For that, you need to vacate pin 3 (your defroster indicator) and move it to pin 5 or 8 which is unused. Then move pin 2 to pin 3. After completing the move, you get turn signal back, but lost high beam and defroster lamp. But won't be for long.

Now you need to rebuild the defroster connection. Look at Jim's pictures and you'll see a solder blob for one end of a jumper wire. This is the ground point we're tapping into. First scrape off some oxidation from both contact points, then stick a lamp holder into the spot so you don't solder too much and prevent you from actually installing a bulb there. Now take a small wire, solder one end to the blob, and the other end to the lower pad. Scrape off the coating off the tip of copper finger of either pin 5 or 8 of C13 above, depending on where the defroster wire is moved to, then solder another wire there. Tack the other end to the defroster spot and you gain it back!

For high beam, solder a wire to the pad similarly to the pad that goes to pin 2, and wire it to ground using the blob above. Now you can put everything back together and everything should work normal. Noticed how I never mentioned cutting traces?

Maybe you should do it for them?

After some more discussion at this newer thread reminded me to look at the gauge cluster wiring once again because another fellow member without a tach scored a 01 cluster with tach and ran into problems again, here are some additional information, including an action plan to get around that issue.

The connectiors are named, starting from the the side with your cruise and door ajar lights among others, as follows, per my 1999 factory diagram:

C11 (it's brown)

C12 (white)

C13 (blue)

C14 (gray)

Pin 6 of C11 has a wired spot available for a lamp that lights up when ignition is ON, and this pin goes to ground. An additional spot below that isn't wired, but once wired, would also light up with under the same condition. Be creative! However the faceplate is black over the area for these two spots. I am still finding out how to put my own icon there.

Pin 9 of C12 is where the factory theft deterrent system indicator LED is wired to. I wanted to find a cluster with tach AND provision to add a module there.

baadpuppy's 3-pin connector "C2" is actually for a bulb check relay, and is the same throughout 98-02.

Now we come to connector C13 and the fun begins.

For 1998-2000 clusters, Pin 1 is high beam, pin 2 is left turn signal, pin 3 is defroster, pin 9 is "4P" signal from your speedo that sends vehicle speed pulse to the engine computer, pin 13 is for right turn signal. The other legs of all these lamps are tied together with pin 12, which is ground.

For 2001-2002 clusters, pin 1 is high beam, pin 2 is return leg of high beam lamp, pin 3 is left turn signal, pin 9 is still 4P, pin 13 is still right turn signal, pin 12 I think is still ground. Only L & R turn lamps are tied together to pin 12; spot for defroster lamp is no longer wired. Thanks Jim for the pics.

If you are installing a 01 cluster, your first priority is to fix the turn signals. For that, you need to vacate pin 3 (your defroster indicator) and move it to pin 5 or 8 which is unused. Then move pin 2 to pin 3. After completing the move, you get turn signal back, but lost high beam and defroster lamp. But won't be for long.

Now you need to rebuild the defroster connection. Look at Jim's pictures and you'll see a solder blob for one end of a jumper wire. This is the ground point we're tapping into. First scrape off some oxidation from both contact points, then stick a lamp holder into the spot so you don't solder too much and prevent you from actually installing a bulb there. Now take a small wire, solder one end to the blob, and the other end to the lower pad. Scrape off the coating off the tip of copper finger of either pin 5 or 8 of C13 above, depending on where the defroster wire is moved to, then solder another wire there. Tack the other end to the defroster spot and you gain it back!

For high beam, solder a wire to the pad similarly to the pad that goes to pin 2, and wire it to ground using the blob above. Now you can put everything back together and everything should work normal. Noticed how I never mentioned cutting traces?

After accidentally purchasing an 01 cluster w/tach for my 99 Corolla. I did a google search and came upon this thread. I downloaded all the pictures that were still available and read what buurin had explained. Then I reread and reread what buurin had explained. After finally deciphering it, I did a little soldering accourding to what was wrote and a little of what I thought would be easier. It worked. I managed to get my 01 cluster working properly on my 99 Corolla.

Basically you build your own leads to the defroster, reconnect the brights lamp wire and left signal wire, and ground the brights lamp wire.

The hardest part was figuring out what buurin was trying to say. He may not have the gift of explaining things well, but he did figure it out. I must give him props for that.

If anyone is interested in this still, I would be happy to post a better step by step procedure on how to do it. Just ask.

M

I having exactly the same problem.

If you still remember, can anybody please write me step by step guide how to fix this issue.

Thank you!

if Guest_MadProps_* is still visiting this forum a step by step guide on how exactly to solder these connections would be awesome

ok, I've laboriously traced out each connection from the connectors to the items they connect to. I did this by drawing a different colored line on each trace in the scans of the circuits.

 

I don't have any official docs (like a factory service manual, or factory wiring diagram), so in the absense of the correct names for the connectory, I simply named them C1 thru C5, with C2 being the 3 pin ABS related connector, counting from left to right with the connectors at the top of the board from the back. In other words, from left to right in the pictures I posted in the previous post. I numbered the pins the same way, from 1 to whatever.

Here are the changes:

C1 pin 9: original goes to: IG+ for Fuel and Temp gauges, and these lamps: CEL, Windshield Washer, O/D off, Oil, Cruise, Seatbelt, Brake. New one goes to: IG+ for Fuel, speedometer, tachometer, and temp gauge. These lamps: CEL, WW, O/D, ABS, Low Gas, Brake, Seatbelt, Oil, Cruise

C2 pin 2: original goes to: C3 pin 2, Rear Defrost Lamp, odd circuit behind speedo, L and R turn signals, High beam. New one goes to: C3 pin 2, odd circuit behind speedo, L and R turn signals.

C3 pin 10: original goes to: SE on speedometer, E on fuel gauge, C4 pin 2. New goes to: C4 pin 2, C4 pin 1, SE on speedometer and fuel and tachometer

C3 pin 11: original goes to: Rear Defrost. New goes to Left Turn Lamp

C3 pin 12: original goes to: Left Turn Lamp. New goes to: high beam other leg.

C4 pin 1: original isn't connected, new is: C4 pin 2, C3 pin 10, SE on speedometer and fuel and tachometer

C4 pin 2: original is: SE on speedometer, E on Fuel Gauge, C3 pin 10. new is: C4 pin 1, C3 pin 10, SE on speedometer, fuel, tachometer.

C4 pin 9: original isn't connected, new is: TAM on tachometer

C4 pin 14: original isn't connected, new is: IG- on tachometer

C5 pin 9: original is +B on speedo, door ajar lamp, new is: +B on speedo, +B on tach, door ajar lamp

I don't think I did any damage with the incorrect cluster in. However, I'm hesitant to try it in the car again. I'm keeping my eye open for a different cluster

I'm wondering if this cluster didn't perhaps come from a different model of toyota. Does anyone know how interchangable they might be? I know the ebayer said it came from a corolla, but you never know. Of course, a different model year might explain it.

jim

I was thinking wrong trim or year. Or maybe it came from a Chevy Prizm? But the Corolla and Prizm gauges, like the cars themselves look alike. I mean, if I see a Prizmoid (my term for Corollas with a Prizm twin) Corolla in a video, the gauge cluster's indistinguishable from the ones in the Prizm. Prizm engine, transmission and electrical mimic the parallel Corollas. Maybe there's some hidden differences between Prizm and Corolla gauges, but from my family's years of Prizm ownership, combined with what I mention here, they look interchangeable.