1999 F250 5.4l Computer Not Ready

Hello All,

I have driven my F250 for about 50 miles and the ECU reads "Not Ready" on my Scan Gauge. I also an intermittent analog instrument cluster. I took the cluster apart and cannot find any bad solder joints, so I am using the San Gauge to read my speed, water temp, voltage, etc.

I get these odd error codes sometimes (upstream O2 sensors swapped, downstream O2 sensor high voltage) that the dealership seems unconcerned about, and of course it did not do it when they had it. The last time that I reset my error codes, the computer never gave me "Ready-No Codes" after I cleared it, even after about 50 miles of driving.

Can the ECU be bad causing my cluster not to work, but still show good values on my scan gauge? Or do I have two different problems?

I really do not want to have a surprise bill when I take it in for our annual safety and emissions test. Unless I take it to a dealership, the garage will charge me for nothing and then tell me to take it to the dealership.

This truck was a plow truck before I bought it, and it has quite a bit of under body rust.

Does anyone know of any specific connectors that get corroded, that can cause anything like I am experiencing?

TIA

Reply to
Gary Ober
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I would expect READY - NO CODES as a normal condition. The other conditions you report sound like a grounding issue, and this is supported by the rust you report.

Remove and clean the ground connections where the battery connects to the block, and where the block and the body connect to the frame rail. Basically, clean the main ground connections because you have far too many different systems affected, so you need a common point among them all. You may have individual ground points that are compromised, but you have to clean the main ground points to reduce the number and broad scope of failures to a few that are confined to a particular area, then clean the ground(s) there.

Me thinks that rust is not your friend ...

Reply to
Jeff Strickland

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