Question: I have a 2003 Chevrolet Express 2500 cargo van with a 5.3-liter V-8, AWD, and 106,000 miles. Over the last several months dating back to last November, I've had an issue with the van starting. Sometimes when I turn the key, nothing happens. Sometimes, though it's rare, I will get a clicking sound from the starter as when the battery is going dead. In either instance, if I continue to try to start the van, it will do the same thing. If, however, I turn the key to the off position and then try to start it again, it will start right up. Just recently, when I turn the key and nothing happens, if I hold the key in the start position, after a few seconds the van will start. Also, occasionally, when I shut the driver's door the door chime will continue to beep. I had a mechanic look at it, and he tested the battery and the starter. Replacing the battery didn't solve the problem. He did a diagnostic check on the van's computer but nothing came up. Every time I have the van in the shop, coincidentally it always starts right up. The only change I made to the van right after I bought it two years ago was to install an aftermarket radio. I know the radio came with an extra part that controlled the door chimes as well as the radio staying on until you open the door. Is this causing the problem, or is it possibly the ignition switch?
| 2003 Chevrolet Express 2500
Answer: There are a couple TSBs dealing with an intermittent no-crank condition on the van in question. One deals with a simple poor connection at a battery terminal, and the other deals with improper installation of the ignition switch. The switch can become "misindexed" one way or the other, which can limit full travel and prevent a start, at times. The fix is proper reinstallation. The starting system works like this: You turn the ignition to start, which sends 12 volts to the PCM. The PCM applies a ground to the starter relay (located in the underhood fuse block). The relay then sends 12 volts to the starter (purple wire), and the engine cranks over. Of course, there may be some complicated stuff preventing operation of the system as a whole, like a poor connection, bad PCM, and so on. But you don't mention replacement of the starter, and it may be as simple as that. Just because it passed the test doesn't mean it's perfect. I always do my best to confirm the cause of an intermittent condition before resorting to an educated-guess part replacement. But sometimes there's no alternative. I suggest you or a technician repeat the starting procedure until you can duplicate the problem; while doing so, have 12-volt test lights connected to the purple wire (ignition feed) and the battery cable connection at the starter. If you turn the key and the engine doesn't crank over, but the test lights light up, you have a bad starter. No light (12 volts) at the purple wire says the problem is in the circuits or components leading back to the ignition switch. No light at the battery cable connection means there's a circuit break at a battery terminal or a power junction block (if equipped).
If you have a technical question regarding your pickup, SUV, or van, feel free to contact Alex, a master technician with the National Institute for Automotive Service Excellence. Send a letter to him in care of Truck Trend Garage, 831 S. Douglas Street, El Segundo, CA 90245, or e-mail us at trucktrend@sourceinterlink.com. Please include the VIN with your question. Due to the volume of questions received every month, we cannot guarantee that everyone's question will be personally answered or will appear in the magazine.
Can't wait for help with a problem you're having with your Truck or SUV? Ask the expert we trust here at Truck Trend Garage -- visit Alex Steele at www.RealWorldAutomotive.com.
