PLEASE HELP! 2.2 problems

[Tylerlp]

so here is whats going on...i have replaced my radiator, thermostat, water pump, coolant temp sensor, and heater core..My temp gauge only goes as high as the 1/4 mark and my heat sucks when im at a stop...i just read through a topic where a guy had a similar problem, but no help there. Also, my SES light stays on constanly and my radiator fan doesnt shut off when the light is on....

[scd88ga]

It could be a bad EPROM (chip) in your ECM (computer).

[DTMAce]

I have a 94 2.2 ECM still that you once asked me for.... Let me know.

[Tylerlp]

well i have tried 2 different computers and 2 different eproms but no change...the scan tool shows a code of a quad driver module failure...oh and ace, sorry haha somebody gave me a computer for free...but i do have a question for you

[scd88ga]

The quad driver is an integrated circuit in the PCM that turns actuators on and off. It is also a safety valve for the electric current in those control circuits. When the quad driver is overheated because of an electrical short in one of those circuits it shuts down the circuit and sends a signal to the main processor in the PCM to illuminate the Malfunction Indicator Lamp ( Service engine soon, or Check engine light). It is designed to help prevent PCM failures caused by shorted solenoids, actuators or wiring.
A code reader will give you the number code and then that can be translated to a DTC description. Example: Quad Driver Module (QDM) B fault is a description. The next step, before buying all the parts that Autozoo has to sell is to have someone diagnose the circuits and components involved. Follow the manufacturer's diagnostic flow chart using the proper tools and equipment to save you money and downtime.

The quad driver generally drives things like relays, solenoids and light bulbs. There are a few things that are easy to check, like the bulbs and relays.

The SES bulb and (I think) "HOT" bulb are driven by this device. You should check that they both come on when you put the car to "on" before starting. Of course, the SES must work, since it came on for you.

Then the A/C relay and Cooling fan relay are driven. For A/C, simply check that your A/C works OK. The relay is pretty silent, unlike some cars, so you can't always hear it click. Just make sure it works. The cooling fan can be checked when you sucked out the code. Since you know how to get the code, you should have noticed that the FAN comes on for a while before getting the code out. (The bulbs also light.) If the fan isn't coming on, check the relay. The Haynes manual probably tells you exactly when the fan comes on during the procedure. The relay is accessible in the under-hood fuse block.

After that, it gets tougher. You have to check some emissions solenoids. From what I've read, the MOST COMMON cause of code 26 is either the EGR solenoid or the canister purge solenoid.

[Tylerlp]

Wow haha yeah it is code 26 so I'll have to start checking all the things connected to that quad driver....I'll keep you updated on my findings

[scd88ga]

LOL! Information overload, can't cumpute! no no buzz buzz smoke...

Yeah, lol! It's something simple causing it, but tracking it down might be a bitch... Good luck!

[Tylerlp]

ok so i checked out both of the solenoids you mentioned and they are both in good working order...so what should i move onto next?

[Tylerlp]

also like i was saying the radiator fan kicks on and stays on about 3-5 seconds after i start the car and as soon as that thing kicks on the SES light also turns on and stays on....A while ago this same thing would happen but the SES light would turn off and so would the fan.

[SuzukiGhostRider]

You said you tried a new ECM. You try a new chip?

[Tylerlp]

Well I've tried the original prom and the one that came with the computer and no difference