Jump to content

1994 chevy 1500 heater control/wipers wont work


Recommended Posts

Posted

i tried to turn my wipers on yesterday, didnt work... just a buzzing noise, then i checked the normal culprit, known defective motor control board, soldered that better, no change, then i noticed when i turn the wiper controls to hi with the key turned back to the accessory position, the ehater controls come on, which werent working before even in run that im aware of though i havent actually double checked to be honest, had little time to play with it and i went straight for wire testing

apon testing some things, ive found that the hot in run wire to the fuse for the heater shows 9.4v on the volt meter when i put the negative lead to it and a pure hot at all times 12v wire on the positive, meaning its almost completely grounded when the truck is in accessory mode, and then when i put the wipers on hi, boom, reading like no voltage when treated like a ground, which i have to assume means it goes hot

im going to check it more thoroughly, find a good ground to test with the right way rather than the ass backwards way i did it lol, but from what i can tell the deal is the hot in run only goes hot when the wipers are engaged on high and the wipers never engage so hopefully someone can tell me somewhere it could have intersected

also, i did some flashing of my ecm, and i have an aftermarket radio, and the radio starts up fine, the ecm i flashed from an $0D BJLH 350 with the 4l60e to an $0E BJKX 454 with the 4l80e, only differences i was aware of between those two ecm programmings though were the transmission which should be perfectly fine im quite sure i got that wiring correct

it shifts fine and everything as far as ive tested though its hard to drive far and fast without an exhaust... kinda risky ya kno

anyway hopefully someone here can help me, and ill do some more testing in a few see what else i can come up with as well as far as other symptoms and more accurate testing of the voltage

Posted

new info gathered, hot when run to wipers seems to be giving 12v to the fuse, but to the fuse on the heater controls i get about 1v unless i have the wiper fuse in and the wipers set to high then it gives 9v and thats enough to engage the controls and light them up... it seems to be using the wipers as a power supply, and no neither of them work when the truck is running either

Posted

heater controls still dont work right though, the power to the hot in run seems to be cut somehow, but unless someone knows whats up with it in the next few days ill probably just end up rigging it somehow, splice it into the known good wiper hot in run or something

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,979
    Total Members
    8,960
    Most Online
    rayredbone
    Newest Member
    rayredbone
    Joined
  • Who's Online   1 Member, 0 Anonymous, 515 Guests (See full list)

  • Latest Articles

  • Posts

    • Question @diyer2 on this line if you please. Are you saying the shudder is the system turning on and off at the frequency of the shudder? Guess I'm asking if you are saying you have seen it do this with the bi-direction scan tool in graph mode? If so have you been able to discern the 'trigger'. Something is telling to cycle rapidly.    My truck just started doing this recently. 197K on the clock. My response has been M5 anything under 55 mph. I treat it like a lugging stick shift. Gear down and let it spin a bit. Engauge M5, then tow mode and then M6 lets the trans stay in 5th but the AFM is active. Smooth like Skippy.    My thought was that as a machine ages the friction gets lower and as the system is load based, the lower friction would allow it to turn on at ever lower rpm until it reaches the lugging point. And yes I am ignorant of any minimum rpm requirement for the system. If you know that would be useful information.    As you know I run a Scan-Gauge II which allows me to watch the On/Off of the signal to the VLOM. While in the shudder mode I'm not seeing is cycle at that frequency or at all for that matter outside the triggers @newdude posted a few years back. Now is it possible that the refresh rate isn't fast enough to catch it? Maybe. It is why I asked my first question about graphing and trigging parameter.     As we have observed from members here the failure point is all over the map miles wise as you note yourself in your opening post. That by itself begs a few questions like fellows that comment on these lifters failing even after the system has been disabled. Long after. 😬   https://www.enginelabs.com/news/tech-tips-replacing-ls-active-fuel-management-lifters-with-melling/   The Gen5 lifters operate the same as the LS versions. In fact they are the same lifter.    https://www.enginelabs.com/tech-stories/sorting-out-gen-v-lt-lifter-failure-with-a-simple-valvetrain-fix/        
    • UPDATE 2: Steering wheel control backlights and control of the cluster can supposedly be achieved by adding a wire to pin 20 of the cluster and tapping it to pin 2 of the main clock spring harness. I'm going to give it a shot - will update  
    • GM Global A pickups 2019-2022 can do OTA programming for the radio.  GM VIP (GM Global B) can do OTAs for almost every module on board.  So a 2022.5 and newer pickup can do OTAs for recalls like the 2.7 fuel flow recall.  EVs get OTAs that improve one pedal driving, radio issues, HVAC issues, updated battery management software, etc.     So age of the vehicle/what GM electrical platform its on will alter what amount of updates can be pushed on OTAs.  
    • Thank You.   So far my new ride is making me look like a genius for going with the 3.0L, as my first fuel refill occurred over three weeks from when I took delivery.  This engine combination is very amazing.  So far no issues and had not done a regen yet.
    • I am curious as to how much fluid you put back in the transmission ( assuming you had replaced the filter to compare to my findings ) and then went through the process of warming up the trans before pulling the check plug to drain out the excess and if you measured how much came back out.    I just found it surprising that some claimed a certain amount less fluid being put in and then draining some back out. The attitude of the truck as per if the surface is level and how the trucks stance is would make quite a difference since the check plug is right at the front of the transmission. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...