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1990 ZR1 no Full power light

All kinds of problems today, I guess by not having the display panel in place I was not getting the display lights to come on, now they are.

I also played with the F3 suspension today and got a truck load of codes. 13, 14, 21, 22, 23, 31, 32, 33, 34, 41, 42, and 43. This tells me that nothing is working. They are timed out and all four are out of position along with the switch being bad and no input for vehicle speed. Sounds like a complete overhaul for that system.

I have been trying to erase the codes for the SIR but have no luck doing it. Is there a trick on counting the 3 seconds and after the last grounding do you turn the key off?

I just went out and erased all the codes and it came back with 12 three times, I started the car the light came on then went out. I did not drive it, is that when they will come on again? This is for the F3
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aj, I've been following this thread from the start. I haven't added anything, because I don't know squat about your problems. :L But, I've been following anyway to see how you are getting along. Hib has been really good with his explanations and guidance. You, my friend, have been a really good student. I love watching threads like this, as this is what CAC is all about. I do believe that you are making progress, and think you will have it under control before long.
Down to the last one.

Hib, I think I am down to my last problem. After I removed all the codes for the ride control when I checked it again there was only code 12 showing and the light goes out.

The same thing happened for the SIR, I made a grounding tool from an old light switch and used a second clock apt and after a couple of tries I erased the codes and rechecked with only code 12.

My last problem is now the ABS system. I have tried to read the codes by grounding A to H but nothing happens. The light just stays on. When I move the car I do not hear the pump come on behind the drivers seat. I have no idea why all these systems were messed up.

Thanks for your help AJ
Ok, so....you got the DIC lights which were not working to come on by removing the DIC panel and disconnecting/reconnecting its harness. That tells me that the connection was dirty or the PC board may have a problem where the connector is on the board. You'll have to road test the car for a while to decide.

As for SRC (you call it "F3" which may be a misidentification of it's RPO FX3). The name of the system is Selective Ride Control and most refer to it as "SRC" or they use the RPO ID. At first you were getting all codes and now you have none. That may have been an anomoly related to pulilng the DIC out. Road test the car for a while and watch the "Service Ride Control" light.

Now...the ABS problem...is it the "ABS Active" light or the "Service ABS" light which stays on?

As for why you are having problems...well...the car is 27 years old. Combine that with maybe some poor maintenance on the part of previous owners and, viola...you have a problem child.

Moving on to some other maintenance issues...have you:

Changes the trans lube, rear axle lube, power steering fluid, coolant and brake fluid? If you haven't since you purchased the car, I'd put those on list.
Hib, The service ABS light is on. I have tried to read the codes by grounding A to H put the light just stays on steady. By reading in the service manual it stated that if any code 41, 45, 55,61 or 63 have been set the light will not blink. This must be what happen and the book says you have to have a Tech1 to find out.

After getting all these issues fixed I was going to ask you what I should use for oil and the rest of the fluids. This car has 27k on it and I have a stack of work orders showing the owner had all kinds of service done on the car. The injectors were changed, the starter twice and the radiator once. The rest of the stuff was routine stuff. There is no mention of the problems that I am having.

Without your help I would not be as far as I am now, thank you very much. AJ
Now things may get a little ugly because of the dumb-assed way Bosch did diagnostics back then

It's true that Bosch ABS II-S has fault codes (DTCs 41, 45, 55, 61 and 63) which only can be read with a scan tester with software which supports 90-91 ABS II S–either a TECH1A with a GM Chassis cartridge which supports 1990, a MasterTech with chasiss software or one of other testers which supports ABS of that vintage. Wose yet, once a repair is made, the only way you can clear those five codes is with a scan tester or by cycling the ignition 100 times.

You can still find used Tech 1A's on the Internet. If you go that route buy one with a Chassis cartridge. You may also be able to find a MasterTech. If you plan on a lot of DIY with the maintenance of that car, a good scan tester will be your friend.

This gets worse... to diagnose those ABS codes, at some stage of the process, you need the J-35592 pin out box to solve them.

DTC 41, 45 and 55 require that pin out box right at the start so you're kind of screwed unless you can find an old J-35592 on the internet, but if you have a 61 or a 63 set, you can try working your way through the diagnostics for those codes until you get to where you need the pin out box.

Now, if you can't get access to the appropriate scan tester, since you don't hear the pump run its self test, you could assume either the pump motor, pump motor relay or the solenoid relay are faulty then do the diagnostics for 61 and 63.

It's very common to have those relays go bad so you could also try "throwing parts" at the problem and just replace those relays.

Another task you can perform is to check all the ABS controller and modulator connections and grounds.

Finally, as to my lubricant recomendations, please, tell me a little about how you drive the car.
Is a Tech1 the same as a Tech1A? They seem to be asking a lot for a tool that works on OB1. If I ever get to drive this thing it will be only on weekends and to a cruise every now and then.
TECH 1 and TECH 1A look the same but the T1A is newer and by far the better of the two.

TECH1s and TECH1As are expensive on the used market because, unlike consumer scan testers, they can support all the controllers in the car and are built to professional standards.

Virtually all the consumer scanners which are OBD (pre-96) do not support ABS.

Whatever you do, if you buy a used tester you want to make sure it supports the chassis control module on a 1990 Corvette.
I don't mean to hijack your thread ajcar, but I'm kind of in the same boat. I recently inherited my father's 1990 ZR1. Everything seemed to be working correctly except the occasional FX3 hiccup. After a couple weeks of driving I have run into some ABS issues. I am waiting on a lateral accelerometer to fix the last code. I did notice when my "service ABS" light came on the "engine full power" light stopped lighting up. I've tried switching the key on during hard acceleration and nothing. I hear all the normal pumps and relays activate at startup. I've also checked the switch to make sure it's operating correctly. Should the "full power" light come on during bulb check? Is it possible for the ABS codes to have disabled full power mode? Any help you all may be able to provide will be very much appreciated.

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