Haltech Control of the A442f (2 Viewers)

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Everything is in and running, haven't driven it yet.Reverse acts funny. I don't have any of the solnoids active for reverse, but it pretty consistently won't shift to reverse from neutral, sometimes from park won't shift, but first gear grabs like a shift kit, so I may try to incorporate the a340 accumulator logic and see what happens, but I have a feeling there is solenoid function for reverse that the FSM doesn't describe.

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Soo, I forgot about getting some data for you on the factory logic. Will do that today!

The timing solenoid on my 93 is not active at all with my 'manual' shift control, it isn't even hooked up so I would doubt it could be your problem. Long shot, double check that the lockup isn't engaged.

Will report with some info this evening on solenoid sequences.
 
There is no solenoid activity in reverse. Have you verified all solenoids are off when trying to shift reverse?

It's easy enough to tell. Pull the plug off the tranny. If reverse works fine then you have something wrong.
 
Soo, I forgot about getting some data for you on the factory logic. Will do that today!

The timing solenoid on my 93 is not active at all with my 'manual' shift control, it isn't even hooked up so I would doubt it could be your problem. Long shot, double check that the lockup isn't engaged.

Will report with some info this evening on solenoid sequences.
Awesome thank you!

No the lock up is not engaged. I'm watching the out puts and the out put logic triggers sol1 when in drive and the trans is definitely in 1st gear when that happens. When in reverse, gear output is recognizing that it is in gear, but all of the solenoid outputs are at a zero state........I should check to make sure that the output floating doesn't leave the relays freaking out.

Anyone have experience with these Hella solid state relays?
 
Awesome thank you!

No the lock up is not engaged. I'm watching the out puts and the out put logic triggers sol1 when in drive and the trans is definitely in 1st gear when that happens. When in reverse, gear output is recognizing that it is in gear, but all of the solenoid outputs are at a zero state........I should check to make sure that the output floating doesn't leave the relays freaking out.

Anyone have experience with these Hella solid state relays?
Are you familiar with solid state relays? They don't work like regular relays do. They require certain loads and polarity regular relays don't care about.

Solid state relays will stick on if you are not using them correctly. I'd bet that's what's happening and why you say reverse works sometimes.
 
Are you familiar with solid state relays? They don't work like regular relays do. They require certain loads and polarity regular relays don't care about.

Solid state relays will stick on if you are not using them correctly. I'd bet that's what's happening and why you say reverse works sometimes.
These relays are setup so they have a 12v in and a chassis ground, they then take a signal ground to trigger the connection. They are a solid state relay inside the form of an ISO relay. This is the most clear document I found to show how to wire them up and is how I have them setup

Hella p/n 931774031 is the part I actually used.

 
These relays are setup so they have a 12v in and a chassis ground, they then take a signal ground to trigger the connection. They are a solid state relay inside the form of an ISO relay. This is the most clear document I found to show how to wire them up and is how I have them setup

Hella p/n 931774031 is the part I actually used.

Just riffing on what Pip was saying, maybe try running a separate ground just temporarily for troubleshooting. More weird problems with electronics can be attributed to grounding than anything I can think of.
 
Ok it's the relays. Transmission works as it should with nothing hooked to it. Set up the relays to test and they don't work.....they just don't work. Switching 12v or switching ground they just toggle between battery voltage and something less than battery voltage. These were supposed be signaled to ground relays

Any thoughts?
 
Ok it's the relays. Transmission works as it should with nothing hooked to it. Set up the relays to test and they don't work.....they just don't work. Switching 12v or switching ground they just toggle between battery voltage and something less than battery voltage. These were supposed be signaled to ground relays

Any thoughts?

It will work great with conventional relays.

Do those Hella relays have a real Datasheet? Real solid state relays are picky that you use them exactly as intended. Every time I've had trouble with them I take another look at the data sheet and realize I missed adding resistors.
 
Ok so testing the relay with a fuel pump, it works just as it should. and the voltage on the load pin pull s to zero.......help out my dumb ME mind. Does this mean the solenoids don't have enough resistance of their own correct? So I need to add a parallel resistor to the solenoid to make them happy?
 
Ok so testing the relay with a fuel pump, it works just as it should. and the voltage on the load pin pull s to zero.......help out my dumb ME mind. Does this mean the solenoids don't have enough resistance of their own correct? So I need to add a parallel resistor to the solenoid to make them happy?


This is why buying real electronic components from reputable companies that provide real datasheets is a good idea.
 

This is why buying real electronic components from reputable companies that provide real datasheets is a good idea.
Thank you for that, confirms where I was going. Now to figure out the resistor. I just measured up the voltage across the shift solenoids and it was floating from 3.5 volts to 10volts. the measured resistance on the solenoids in 30ohm, so 300ma isn't enough to turn off the solenoid. Any idea how to calculate what resistor would be enough?
 
Measure the voltage at the output of the relays when they are off. <- Scratch that, just found out you did.

I can guarantee that it is not the timing solenoid.

Here are two and a half senarios.

My old 93 with a diesel, setup with electric manual shifting. Logic as follows;

0-Off
1-On

Gear, S1, S2, ST, SL
P -> 0, 0, 0, 0
R-> 0, 0, 0, 0
N-> 0, 0, 0, 0
D-> 0, 0, 0, 0 <- OD ON
D-> 0, 1, 0, 0 <- OD OFF
2-> 1, 1, 0, 0
1-> 1, 0, 0, 0

SL is controlled manually via an external switch, and ST has never been hooked up. This has worked for almost 10 years

Now to complicate things. I rigged up some LED's to each solenoid, though I was recording the patterns as driving but managed to only take a picture...

Vechicle stopped

Gear, S1, S2, ST, SL
P-> 1, 1, 0, 0
R-> 0, 1, 0, 0 <- for five seconds, then all solenoids turn off.
N-> 0, 1, 0, 0
D-> 1, 0, 0, 0
2-> 1, 0, 0, 0
1-> 1, 0, 0, 0

This surprised me some, but it works.

Now while driving SL will come on before a shift til after the shift completes. Only from 1->2, 2->3, 3->4, 4->3, 3->2. The on time is different and seems to be slightly dependent on gear change and throttle position. This is from slight acceleration to WOT acceleration. Shift point didn't really follow any of the timing, just while SL was energized.

For funsies I pulled the pin for SL, stuck a resistor across the pin to ground and drove. Basically tricking the TCM and disabling SL, basically it shifted the same. Maybe slightly quicker and firmer but had to really 'feel' it.

I'll try to find my logger, if not will build another for some more data in the next couple of weeks.
 
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Thank you for that, confirms where I was going. Now to figure out the resistor. I just measured up the voltage across the shift solenoids and it was floating from 3.5 volts to 10volts. the measured resistance on the solenoids in 30ohm, so 300ma isn't enough to turn off the solenoid. Any idea how to calculate what resistor would be enough?
Wire two of the solenoid to the same relay and see if the voltage goes from floating to ground with the relay off, if its still floating with two add another. Then measure the resistance it takes to bring it to ground. I bet 15ohms will do it.

Make sure your wattage of the resistors you buy is plenty overkill, and in some airflow if you can after you determine the required resistance.
 
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Measure the voltage at the output of the relays when they are off. <- Scratch that, just found out you did.

I can guarantee that it is not the timing solenoid.

Here are two and a half senarios.

My old 93 with a diesel, setup with electric manual shifting. Logic as follows;

0-Off
1-On

Gear, S1, S2, ST, SL
P -> 0, 0, 0, 0
R-> 0, 0, 0, 0
N-> 0, 0, 0, 0
D-> 0, 0, 0, 0 <- OD ON
D-> 0, 1, 0, 0 <- OD OFF
2-> 1, 1, 0, 0
1-> 1, 0, 0, 0

SL is controlled manually via an external switch, and ST has never been hooked up. This has worked for almost 10 years

Now to complicate things. I rigged up some LED's to each solenoid, though I was recording the patterns as driving but managed to only take a picture...

Vechicle stopped

Gear, S1, S2, ST, SL
P-> 1, 1, 0, 0
R-> 0, 1, 0, 0
N-> 0, 1, 0, 0
D-> 1, 0, 0, 0
2-> 1, 0, 0, 0
1-> 1, 0, 0, 0

This surprised me some, but it works.

Now while driving SL will come on before a shift til after the shift completes. Only from 1->2, 2->3, 3->4, 4->3, 3->2. The on time is different and seems to be slightly dependent on gear change and throttle position. This is from slight acceleration to WOT acceleration. Shift point didn't really follow any of the timing, just while SL was energized.

For funsies I pulled the pin for SL, stuck a resistor across the pin to ground and drove. Basically tricking the TCM and disabling SL, basically it shifted the same. Maybe slightly quicker and firmer but had to really 'feel' it.

I'll try to find my logger, if not will build another for some more data in the next couple of weeks.
Thank you, thank you!

I the logic I have in the haltech for the solenoid operation is the same as you have. The first thing I did was disable the st output and you are right nothing changed. Best I can guess is that it acts like accumulator solenoid on the A342, but not maybe, since it is wired differently. The 342 uses pwm control for accumulator solenoid, lockup solenoid, and pressure control solenoid and they are wired in a return loop to the ecu the s1 and s2 solenoids go to chassis ground just like the A442.......so I'll just abandon the st solenoid for now.

The S1, S2 and SL out puts are set to be just 12v when signaled.

I did find in the troubleshooting guide in the FSM where voltage across S1 with the engine running, in neutral, should be battery voltage.

I tried wiring up two of the solenoids together, the float voltage went down, but it did not turn off. Maybe it's the type of load that the solenoid presents? I tried straight grounding the output.......that didn't work. So I'll try to find some resistors and see what pulls the relay to turn off.
 
So figured out the solid state relay problem. It's the presence of the driver from the Haltech in the circuit. A pull up resistor needs to be placed from 12v to the haltech driver. I am using Injector #7 and #8, and Ignition #7 and #8 for the transmission control. Found a random 1.5kohm floating around in the shop, and tried it......and it worked.

Haltech sells a high amp solid state relay for fans and the like and they show (and include with the relay) a 1kohm resistor in the schematic for that. So........

Hopefully I'm driving this to work on Tuesday
 

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