more wiper and washer motor fun

[gmbellew]

I had previously had issues with the delay wipers on the 1990 suburban. The pulse module and switch were replaced, but were not the culprit. it was the motor that needed to be replaced. Likely the onboard circuit break was getting weak or the park switch bad. All was good for 6 months or so.

Now I have an issue where sporadically the intermittent doesn't behave properly and/or the washer pump doesn't work (or start the low speed wiper for 6 sec).

once when the washer pump/6 sec low speed wasn't working, I was able to check for power and ground at the pump. I had constant power, but no ground at the pump with the switch pressed. then I swapped the pulse board, but the pump/6sec low speed still didn't work.

sometimes it all works, sometimes the delay goes funky, sometimes the washer pump/6sec low doesn't work, and sometimes they both don't work. It seems random. today it is the delay issue only, for those that are interested.

the only place these two circuits share anything is 1) at the pulse board, 2) at the switch and 3) at the common ground leaving the pulse module.

the pulse board seems OK, it was swapped with a good one and no change.

if the common ground leaving the pulse board was bad was bad, it seems that I would have no wipers. also, I can look up and see the ground bus bar and it looks clean and tidy up there.

So that leaves just the switch (a new one is on order) that could be bad.

I wondered if anybody had any other thoughts, or had seen a similar issue, before I get the switch replaced when it comes in?

 

[SirRobyn0]

There is a HUGE problem with defect reman wiper motors with these rigs. If you bought a reman I'd be concerned about that. I'm not someone that is normally adverse to reman products but where it comes to these wiper motors I am. If you would like I can recommend new wiper motor brands we have had good luck with at the shop.

Wiper motor ground. There is a ground tab from the body of the wiper motor to one of the mount bolts. The mounts are rubber to prevent excessive noise and vibration from traveling out of the motor and into the cab. Those ground tabs are notorious for causing weird intermittent problems that don't seem to have a cause. Those tabs need to be dang near perfect to. Make sure it isn't beat up and is tight where it is riveted to the motor. On the mount side it needs to have a good clean contact to the bolt and even the bolt threads need to be clean. Sometimes at the shop we have had to resort to attaching a separate wire from the body of the wiper motor to one of the mount bolts with a eyelet connector. If you have it failing in someway right now you outta take a spare wire and attached to a good clean unpainted surface on the wiper motor and run it directly to the battery negative and see if the wipers start to work normally, if they do it's something in that ground. If they don't then that's not likely the problem.

I don't know much about the pulse boards so I'm not going to be able to help much with that, but it seems to me that they usually work or they don't. I can't recall in recent memory anyway one that would work fine one time and then not work correctly the next time. Ditto on the wiper switch.

Hopefully something in there will be helpful.

 

[WP29P4A]

There is a HUGE problem with defect reman wiper motors with these rigs. If you bought a reman I'd be concerned about that. I'm not someone that is normally adverse to reman products but where it comes to these wiper motors I am. If you would like I can recommend new wiper motor brands we have had good luck with at the shop.

Wiper motor ground. There is a ground tab from the body of the wiper motor to one of the mount bolts. The mounts are rubber to prevent excessive noise and vibration from traveling out of the motor and into the cab. Those ground tabs are notorious for causing weird intermittent problems that don't seem to have a cause. Those tabs need to be dang near perfect to. Make sure it isn't beat up and is tight where it is riveted to the motor. On the mount side it needs to have a good clean contact to the bolt and even the bolt threads need to be clean. Sometimes at the shop we have had to resort to attaching a separate wire from the body of the wiper motor to one of the mount bolts with a eyelet connector. If you have it failing in someway right now you outta take a spare wire and attached to a good clean unpainted surface on the wiper motor and run it directly to the battery negative and see if the wipers start to work normally, if they do it's something in that ground. If they don't then that's not likely the problem.

I don't know much about the pulse boards so I'm not going to be able to help much with that, but it seems to me that they usually work or they don't. I can't recall in recent memory anyway one that would work fine one time and then not work correctly the next time. Ditto on the wiper switch.

Hopefully something in there will be helpful.

I was in the middle of typing the same thing when you posted this. Is the ground between the back of engine and firewall still attached?

 

[gmbellew]

the motor IS a cardone rebuild. but the motor wiring does not provide power or ground to the washer that I can tell.

I have poured over the 1990 wiring diagrams and they do not indicate there is a body ground on the wiper motor. the diagrams show the wiper and washer pump both get constant 12v from the fuse box. ground, for the various wiper modes and washer, is provided by the switch for the entire system. the switched grounds all run back through the pulse board and to the ground bar up above the e brake.

I just went out now, and washer and delay are not working. I tried looking for a motor ground, but didn't see anything with a flashlight. is it integral with the mount bolts and passes through the rubber or a separate tab? I tried manipulating the motor position, trying to get a better ground, and it didn't help.

I will have to check out the motor mounts better, look for a wiper ground, and check the block-to-firewall ground tomorrow in the daylight. maybe try to ground the motor to the battery and see if that does anything.

 

[SirRobyn0]

You must be registered for see images attach

That is a picture of a A1 Cardone or Cardone wiper motor for a 1990 suburban off the O'rielly's website. See that copper / brass looking thing? That's the wiper ground. Now I've not taken the actual motor end of one of these wipers apart but my understanding is that yes, the switch controls the ground for the circuit inside the motor, but the motor is grounded though that tab, whatever or however the details there are is unimportant though, what I do know for 100% beyond a shadow of a doubt is that if that ground tab has an issue (outlined in my previous post) or if it's missing all together it'll cause weird problems is the electricity will find other paths to ground though or the motor simply won't work.

It's either that or you have an odd switch failure and given where the switch is I'd think you'd wanna check the easy common stuff first.

Also as I said you could connect a ground wire with some extra wire you have laying around from a good clean metal part on the wiper motor to the negative terminal on the battery as a test to see if it starts working right.

I am not 100% sure on how the washers are activated after 84 when they got the separate electric pump, but there has to be some connection to the motor somewhere, so if it were me I'd tackle the motor issues first, and then see if the washer issue persists.

I probably said this to you before but we won't install cardone parts at the shop anymore due do to many comebacks from there terrible rebuilds.

 

[SirRobyn0]

I was in the middle of typing the same thing when you posted this. Is the ground between the back of engine and firewall still attached?

Sorry about that. It seems like you and I think along the same lines often times.

 

[gmbellew]

I just ran out and checked. my wiper motor has the tab for that strap to attach, but has no strap. I don't believe it came with one. I will use some spare wire to go from the bottom bolt to a good ground and see if that fixes the delay issue. if so, I'll mimic the strap in the picture and use the mounting tab and hopefully not have more issues.

if that doesn't fix it, I am out of ideas except the switch...which as you have said, is not quick to replace.

 

[gmbellew]

oh, regarding power to the wiper motor and washer pump - they "shouldn't" be connected per the diagrams, unless the power is spliced off after the wiper motor (not what is shown) OR somehow the wiper motor body ground is integral somehow to the entire system

 

[SirRobyn0]

I just ran out and checked. my wiper motor has the tab for that strap to attach, but has no strap. I don't believe it came with one. I will use some spare wire to go from the bottom bolt to a good ground and see if that fixes the delay issue. if so, I'll mimic the strap in the picture and use the mounting tab and hopefully not have more issues.

if that doesn't fix it, I am out of ideas except the switch...which as you have said, is not quick to replace.

Ah ha, I'd be willing to bet you just found the problem, at least the wiper problem. Like I said i really have no idea on the washer, but if the washer is run though the pulse module, the pulse module may need to some sort of feedback from the wipers to turn the washer on. Regardless if you get the wipers nailed down, I think troubleshooting the washer motor will be relatively easier.

 

[AuroraGirl]

There is a HUGE problem with defect reman wiper motors with these rigs. If you bought a reman I'd be concerned about that. I'm not someone that is normally adverse to reman products but where it comes to these wiper motors I am. If you would like I can recommend new wiper motor brands we have had good luck with at the shop.

Wiper motor ground. There is a ground tab from the body of the wiper motor to one of the mount bolts. The mounts are rubber to prevent excessive noise and vibration from traveling out of the motor and into the cab. Those ground tabs are notorious for causing weird intermittent problems that don't seem to have a cause. Those tabs need to be dang near perfect to. Make sure it isn't beat up and is tight where it is riveted to the motor. On the mount side it needs to have a good clean contact to the bolt and even the bolt threads need to be clean. Sometimes at the shop we have had to resort to attaching a separate wire from the body of the wiper motor to one of the mount bolts with a eyelet connector. If you have it failing in someway right now you outta take a spare wire and attached to a good clean unpainted surface on the wiper motor and run it directly to the battery negative and see if the wipers start to work normally, if they do it's something in that ground. If they don't then that's not likely the problem.

I don't know much about the pulse boards so I'm not going to be able to help much with that, but it seems to me that they usually work or they don't. I can't recall in recent memory anyway one that would work fine one time and then not work correctly the next time. Ditto on the wiper switch.

Hopefully something in there will be helpful.

do you think this motor has the same mounting provisions, even if it wouldnt be "turned" the proper way on the firewall? I was looking at some squarebody motors
i WONDer if post 87 car or truck wiper motors(with pulse, so multiplex and all that) could be put on squares.

 

[AuroraGirl]

I had previously had issues with the delay wipers on the 1990 suburban. The pulse module and switch were replaced, but were not the culprit. it was the motor that needed to be replaced. Likely the onboard circuit break was getting weak or the park switch bad. All was good for 6 months or so.

Now I have an issue where sporadically the intermittent doesn't behave properly and/or the washer pump doesn't work (or start the low speed wiper for 6 sec).

once when the washer pump/6 sec low speed wasn't working, I was able to check for power and ground at the pump. I had constant power, but no ground at the pump with the switch pressed. then I swapped the pulse board, but the pump/6sec low speed still didn't work.

sometimes it all works, sometimes the delay goes funky, sometimes the washer pump/6sec low doesn't work, and sometimes they both don't work. It seems random. today it is the delay issue only, for those that are interested.

the only place these two circuits share anything is 1) at the pulse board, 2) at the switch and 3) at the common ground leaving the pulse module.

the pulse board seems OK, it was swapped with a good one and no change.

if the common ground leaving the pulse board was bad was bad, it seems that I would have no wipers. also, I can look up and see the ground bus bar and it looks clean and tidy up there.

So that leaves just the switch (a new one is on order) that could be bad.

I wondered if anybody had any other thoughts, or had seen a similar issue, before I get the switch replaced when it comes in?

how about the contacts between the board on the pump outside and the motor. on a non pulse one these are connected externally but the pulse board has 2 connecotr things that join the contact

 

[gmbellew]

I ran a ground from the tab on the wiper to the battery. it did not change the operation or correct the issue.

 

[AuroraGirl]

I ran a ground from the tab on the wiper to the battery. it did not change the operation or correct the issue.

that doesnt answer my question

 

[gmbellew]

that doesnt answer my question

I was responding to SirRobyn0. I am not sure I understand your question. the pulse module is at the base of the steering column. it's connections seem OK and I swapped modules and it didn't change anything with the wipers or washer.

the washer has 2 wires - constant hot from the fuse box and a ground that goes to the switch.

the wiper motor is a little more complicated. but it has 12v constant power from the same fuse as the washer and then various switched grounds and jumpers associated with hi/lo and park.

both wiper and washer are getting their power.

washer has no ground through the switch. washer switch doesn't wash and doesn't start the wipers on low for 6sec.

delay mode isn't operating properly on the wipers. low and hi seem to work OK.

grounding the wiper motor case to the battery didn't do anything.

the ground strap from engine to firewall is present and has a good connection.

 

[SirRobyn0]

I was responding to SirRobyn0. I am not sure I understand your question. the pulse module is at the base of the steering column. it's connections seem OK and I swapped modules and it didn't change anything with the wipers or washer.

the washer has 2 wires - constant hot from the fuse box and a ground that goes to the switch.

the wiper motor is a little more complicated. but it has 12v constant power from the same fuse as the washer and then various switched grounds and jumpers associated with hi/lo and park.

both wiper and washer are getting their power.

washer has no ground through the switch. washer switch doesn't wash and doesn't start the wipers on low for 6sec.

delay mode isn't operating properly on the wipers. low and hi seem to work OK.

grounding the wiper motor case to the battery didn't do anything.

the ground strap from engine to firewall is present and has a good connection.

I understand what you are saying but the missing ground tab is an issue. I'm not trying to be diffecult but they do put those on for a reason. Given that it's a new motor and that is missing do you still have a warrenty? Maybe it would be a good idea to swap it out. I don't know, I'm just not very trusting of cardone to begin with and then a motor with missing ground to boot.