Problem with $wpdb->get_var

Can anyone PLEASE tell me why the following won’t work?

I’m tearing my hair out here – I’m assuming I have a typo but not sure.

function cat_has_products($id) {
	global $wpdb;
	$id = trim($id);

	$sql = "SELECT term_taxonomy_id from wp_term_taxonomy where term_id = $id;";
	$termtaxid = $wpdb->get_var ($wpdb->prepare( $sql) );
	echo "ID = $id <br>";
	echo "Term id = $termtaxid <br>" ;
	$catprodcount = $wpdb->get_var ($wpdb->prepare( "select count(object_id) from $wpdb->term_relationships where term_taxonomy_id = $termtaxid;") );
	echo "Count is : <br>" . $catprodcount;
	//return $catprodcount;

}

Typical output is as follows

ID = 96
Term id =
Count is :

where 96 is the value passed to the function.