Wiring Gurus - Help Needed!
09-05-16, 02:46 PM
#27
So, fixed a few issues. Solved my brake warning light wiring problem (had a power wire back feeding into the ground) and the brake pedal problem priming the fuel pump. Had the new brake light modules wired into a spare Haltech ECU ignition on source which should have worked but for some reason, caused the problem. Traced down an independent - as in didn't seem to mess with any other systems - ignition wire in the center console and rewired the brake modules to there. Problem solved.
Finally, I ordered new capacitors for the CPU #2, in hopes that will solve my seat belt warning light.
Finally, I ordered new capacitors for the CPU #2, in hopes that will solve my seat belt warning light.
09-05-16, 05:20 PM
#28
Super Moderator
iTrader: (1)
David,
Good work fixing the brake and fuel pump wiring problems. That's interesting that you had to find an independent ignition power wire. Then again, I am unfamiliar with the Halitech ECU wiring.
What capacitors did you have to order from the CPU? Do you have any photos to share of the CPU board?
Good work fixing the brake and fuel pump wiring problems. That's interesting that you had to find an independent ignition power wire. Then again, I am unfamiliar with the Halitech ECU wiring.
What capacitors did you have to order from the CPU? Do you have any photos to share of the CPU board?
09-05-16, 06:17 PM
#29
Yep thought there would be no issues wiring into the Haltech system but it didn't work. Well, if triggering the fuel prime system is not a problem then all was just fine. 
As for CPU #2, I will take pics but haven't taken it out yet to inspect. My symptoms seem to point to the unit so I am betting on it. I went ahead and ordered replacements for the major capacitors following Smokey's list he posted in another thread. Going to replace them all since they are dirt cheap
Drove the car today and noted the adjust mirror system is not working. Strangely when I activate the adjustment switch the radio turns off. Another thing to add to the list.
As for CPU #2, I will take pics but haven't taken it out yet to inspect. My symptoms seem to point to the unit so I am betting on it. I went ahead and ordered replacements for the major capacitors following Smokey's list he posted in another thread. Going to replace them all since they are dirt cheap
Drove the car today and noted the adjust mirror system is not working. Strangely when I activate the adjustment switch the radio turns off. Another thing to add to the list.
09-09-16, 05:41 PM
#30
CPU #2 update. Unit is now repaired and operating normally. I removed the CPU from the driver's side footwell area and opened it up for inspection. Capacitors #2 and 5 were bad - they had unattached from the circuit board.
Removed them with desoldering braid from Radio Shack and soldered in new replacements from the Amazon kit I bought. All warning lights now working normally!
A pic of CPU #2 and the capacitor kit from Amazon:
Pic of the two circuit boards found in the CPU. The suspect caps are the ones with the silver tops and are marked C1-7:
Look on the board and you will see the "C" markings for the capacitors. Smokey posted up the values for each on the forum (or you can find that on the side of the caps). Also note the white directional markings on the board as you use these as a guide for reinstalling the capacitors in the correct position:
Not all that hard to do with a little patience and the right tools (soldering iron and desoldering braid).
With the CPU fixed, now I am left with a headlight issue, as in they don't work when activating the steering wheel stalk. The retractor button raises them up and down and the pass to flash option (pull the stalk bak) operates the high beams so I have ruled out fuses. I have also checked all the relays and they seem to be fine but have ordered replacements for the relays just in case I am missing something.
Will be back at it tomorrow to test the switch and then go from there.
Removed them with desoldering braid from Radio Shack and soldered in new replacements from the Amazon kit I bought. All warning lights now working normally!
A pic of CPU #2 and the capacitor kit from Amazon:
Pic of the two circuit boards found in the CPU. The suspect caps are the ones with the silver tops and are marked C1-7:
Look on the board and you will see the "C" markings for the capacitors. Smokey posted up the values for each on the forum (or you can find that on the side of the caps). Also note the white directional markings on the board as you use these as a guide for reinstalling the capacitors in the correct position:
Not all that hard to do with a little patience and the right tools (soldering iron and desoldering braid).
With the CPU fixed, now I am left with a headlight issue, as in they don't work when activating the steering wheel stalk. The retractor button raises them up and down and the pass to flash option (pull the stalk bak) operates the high beams so I have ruled out fuses. I have also checked all the relays and they seem to be fine but have ordered replacements for the relays just in case I am missing something.
Will be back at it tomorrow to test the switch and then go from there.
09-09-16, 06:49 PM
#31
Super Moderator
iTrader: (1)
David,
Here are 2 probable areas to check out:
1. Output from Electrical Load Control Unit (black box next to ECU) (from B-1b of wiring FSM).
2. Output from CPU #2 (from J-4 of wiring FSM).
Did you see any thing else wrong with CPU#2 such as cold solder joints or other leaky caps?
You can also check the Terminal Voltage List from J-4 of wiring FSM, check out any TNS Relay or Headlight relay/HEAD circuits.
BTW, there looks like more damage below C3. Care to take more pics of your CPU #2? You may have to move the board around and check it out from all angles to see any unusual joints or leaky caps.
Here are 2 probable areas to check out:
1. Output from Electrical Load Control Unit (black box next to ECU) (from B-1b of wiring FSM).
2. Output from CPU #2 (from J-4 of wiring FSM).
Did you see any thing else wrong with CPU#2 such as cold solder joints or other leaky caps?
You can also check the Terminal Voltage List from J-4 of wiring FSM, check out any TNS Relay or Headlight relay/HEAD circuits.
BTW, there looks like more damage below C3. Care to take more pics of your CPU #2? You may have to move the board around and check it out from all angles to see any unusual joints or leaky caps.
Last edited by Gen2n3; 09-09-16 at 06:52 PM.
09-10-16, 09:05 AM
#32
^ You are right, C3 looks bad. As for cold solder joints, I am going to remove the CPU and inspect again. I think I will go ahead and replace all of the capacitors as I have new ones here so why not?
As for the headlight issue, the electrical troubleshooting manual has me looking at other things than what you have suggested. I have attached those portions of the manual. In particular, I have performed the steps on E19 and I am not getting voltage at terminal A. Not sure if I should see voltage at C & E, but I do, just not A. So I am going to check the wiring between the headlight relay and the retractor relay.
The tricky thing for me is I have retrofitted the lights with sleepy eye protector hid popups so it's not quite stock in the setup. I am going to call Kilo Racing - the group that did the work - to discuss.
As for the headlight issue, the electrical troubleshooting manual has me looking at other things than what you have suggested. I have attached those portions of the manual. In particular, I have performed the steps on E19 and I am not getting voltage at terminal A. Not sure if I should see voltage at C & E, but I do, just not A. So I am going to check the wiring between the headlight relay and the retractor relay.
The tricky thing for me is I have retrofitted the lights with sleepy eye protector hid popups so it's not quite stock in the setup. I am going to call Kilo Racing - the group that did the work - to discuss.
09-10-16, 10:50 AM
#33
So, there are a number of suspect 4 band resistors on the board. For whatever reason, my camera won't zoom in and take a decent shot so can't post up anything.
Took the board to Radio Shack and the person there identified several other suspect areas. We counted a total of 9 resistors that need replacing. I concur with the salesperson that should I fix these, then it is likely others will have issues so I am going to replace CPU #2 with a new unit.
Don't want to spend the $250 on a new unit but I am going to bite the bullet as it is likely a used unit will have or develop the same problems. Guess this one lasted 22 years and I'd be happy with the new one lasting as long.
So, it's now on to tackle the headlight issue.
Took the board to Radio Shack and the person there identified several other suspect areas. We counted a total of 9 resistors that need replacing. I concur with the salesperson that should I fix these, then it is likely others will have issues so I am going to replace CPU #2 with a new unit.
Don't want to spend the $250 on a new unit but I am going to bite the bullet as it is likely a used unit will have or develop the same problems. Guess this one lasted 22 years and I'd be happy with the new one lasting as long.
So, it's now on to tackle the headlight issue.
09-10-16, 03:41 PM
#34
Super Moderator
iTrader: (1)
David,
First, I am surprised that someone in Radio Shack was able to help identify bad components! Are you certain that the resistors need to be replaced? Or could there be bad solder joints such as leakage from caps? When a resistor is bad, you know it! It will blow open and release the magic smoke.
I could potentially help in repairing the board so long as all the parts are identified. If you still have my number then give me a call and we could talk about it further.
Cheers,
George
First, I am surprised that someone in Radio Shack was able to help identify bad components! Are you certain that the resistors need to be replaced? Or could there be bad solder joints such as leakage from caps? When a resistor is bad, you know it! It will blow open and release the magic smoke.
I could potentially help in repairing the board so long as all the parts are identified. If you still have my number then give me a call and we could talk about it further.
Cheers,
George
09-10-16, 05:22 PM
#35
I will call you George. Several of the resistors are blown as in they have holes in their sides. The others have very suspect solder joints.
I am tired today as I spent a good bit of time trying to diagnose the headlight issue. That led me to under the dash where I found some crappy wiring from a mechanic (not Kilo) that I now need to repair. I then pulled the radio head unit to inspect the wiring there and it is bad. Still not grounded properly. So I am calling it for tonight and going to watch some football.
I am tired today as I spent a good bit of time trying to diagnose the headlight issue. That led me to under the dash where I found some crappy wiring from a mechanic (not Kilo) that I now need to repair. I then pulled the radio head unit to inspect the wiring there and it is bad. Still not grounded properly. So I am calling it for tonight and going to watch some football.
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